FIRST LIEN SUBSIDIARY GUARANTY Dated as of July 31, 2007 From THE GUARANTORS NAMED HEREIN and THE ADDITIONAL GUARANTORS REFERRED TO HEREIN as Guarantors in favor of THE SECURED PARTIES REFERRED TO IN THE CREDIT AGREEMENT REFERRED TO HEREIN

Exhibit 10.66

EXECUTION COPY

FIRST LIEN SUBSIDIARY GUARANTY

Dated as of July 31, 2007

From

THE GUARANTORS NAMED HEREIN

and

THE ADDITIONAL GUARANTORS REFERRED TO HEREIN

as Guarantors

in favor of

THE SECURED PARTIES REFERRED TO IN
THE CREDIT AGREEMENT REFERRED TO HEREIN

TABLE OF CONTENTS

Section				Page
Section 1.		Guaranty; Limitation of Liability			1
Section 2.		Guaranty Absolute			2
Section 3.		Waivers and Acknowledgments			3
Section 4.		Subrogation			4
Section 5.		Payments Free and Clear of Taxes, Etc.			5
Section 6.		Representations and Warranties			5
Section 7.		Covenants			5
Section 8.		Amendments, Guaranty Supplements, Etc.			5
Section 9.		Notices, Etc.			6
Section 10.		No Waiver; Remedies			6
Section 11.		Right of Set-off			6
Section 12.		Indemnification			7
Section 13.		Subordination			7
Section 14.		Continuing Guaranty; Assignments under the Credit Agreement			9
Section 15.		Execution in Counterparts			9
Section 16.		Governing Law; Jurisdiction; Waiver of Jury Trial, Etc.			9
Exhibit A — Guaranty Supplement

FIRST LIEN SUBSIDIARY GUARANTY

     FIRST LIEN SUBSIDIARY GUARANTY dated as of July 31, 2007 made by the Persons listed on the signature pages hereof under the caption “Subsidiary Guarantors” and the Additional Guarantors (as defined in Section 8(b)) (such Persons so listed and the Additional Guarantors being, collectively, the “Guarantors” and, individually, each a “Guarantor”) in favor of the Secured Parties (as defined in the Credit Agreement referred to below).

     PRELIMINARY STATEMENT. Terremark Worldwide, Inc., a Delaware corporation (the “Borrower”), is party to a First Lien Senior Secured Credit Agreement dated as of July 31, 2007 (as amended, amended and restated, supplemented or otherwise modified from time to time, the “Credit Agreement”; the capitalized terms defined therein and not otherwise defined herein being used herein as therein defined) with certain Lenders party thereto, and Credit Suisse, acting through one or more of its branches (“Credit Suisse”), as Administrative Agent and as Collateral Agent for such Lenders. Each Guarantor, as a subsidiary of the Borrower, is engaged in a related and mutually interdependent business with the Borrower and, as a consequence, will derive substantial direct and indirect financial and business advantages and benefits from the transactions contemplated by the Credit Agreement, including Borrower’s receipt of the funds contemplated thereby. It is a condition precedent to the making of Term Loans by the Lenders under the Credit Agreement and the entry by the Hedge Banks into Secured Hedge Agreements from time to time that each Guarantor shall have executed and delivered this Guaranty.

     NOW, THEREFORE, in consideration of the premises and in order to induce the Lenders to make Term Loans under the Credit Agreement and the Hedge Banks to enter into Secured Hedge Agreements from time to time, each Guarantor, jointly and severally with each other Guarantor, hereby agrees as follows:

     Section 1. Guaranty; Limitation of Liability. (a) Each Guarantor hereby absolutely, unconditionally and irrevocably guarantees the punctual payment when due, whether at scheduled maturity or on any date of a required prepayment or by acceleration, demand or otherwise, of all Obligations of each other Loan Party now or hereafter existing under or in respect of the Loan Documents (including, without limitation, any extensions, modifications, substitutions, amendments or renewals of any or all of the foregoing Obligations), whether direct or indirect, absolute or contingent, and whether for principal, interest, premiums, fees, indemnities, contract causes of action, costs, expenses or otherwise (such Obligations being the “Guaranteed Obligations”), and agrees to pay any and all expenses (including, without limitation, fees and expenses of counsel) incurred by the Administrative Agent or any other Secured Party in enforcing any rights under this Guaranty or any other Loan Document. Without limiting the generality of the foregoing, each Guarantor’s liability shall extend to all amounts that constitute part of the Guaranteed Obligations and would be owed by any other Loan Party to any Secured Party under or in respect of the Loan Documents but for the fact that they are unenforceable or not allowable due to the existence of a bankruptcy, reorganization or similar proceeding involving such other Loan Party. This Guaranty is a guaranty of payment and not of collection.

     (b) Each Guarantor, and by its acceptance of this Guaranty, the Administrative Agent and each other Secured Party, hereby confirms that it is the intention of all such Persons that this Guaranty and the Obligations of each Guarantor hereunder not constitute a fraudulent transfer or conveyance for purposes of any Bankruptcy Law (as defined below), the Uniform Fraudulent Conveyance Act, the Uniform Fraudulent Transfer Act or any similar foreign, federal or state law to the extent applicable to this Guaranty and the Obligations of each Guarantor hereunder. To effectuate the foregoing intention, the Administrative Agent, the other Secured Parties and the Guarantors hereby irrevocably agree that the Obligations of each Guarantor under this Guaranty at any time shall be limited to the maximum amount as will result in the Obligations of such Guarantor under this Guaranty not constituting a fraudulent transfer or conveyance. For purposes hereof, the term “Bankruptcy Law” means any proceeding of the type referred to in Section 8.01(f) or (g) of the Credit Agreement or Title 11, U.S. Code, or any similar foreign, federal or state law for the relief of debtors.

     (c) Each Guarantor hereby unconditionally and irrevocably agrees that in the event any payment shall be required to be made to any Secured Party under this Guaranty or any other guaranty, such Guarantor will contribute, to the maximum extent permitted by law, such amounts to each other Guarantor and each other guarantor so as to maximize the aggregate amount paid to the Secured Parties under or in respect of the Loan Documents.

     Section 2. Guaranty Absolute. Each Guarantor guarantees that the Guaranteed Obligations will be paid strictly in accordance with the terms of the Loan Documents, regardless of any law, regulation or order now or hereafter in effect in any jurisdiction affecting any of such terms or the rights of any Secured Party with respect thereto. The Obligations of each Guarantor under or in respect of this Guaranty are independent of the Guaranteed Obligations or any other Obligations of any other Loan Party under or in respect of the Loan Documents, and a separate action or actions may be brought and prosecuted against each Guarantor to enforce this Guaranty, irrespective of whether any action is brought against the Borrower or any other Loan Party or whether the Borrower or any other Loan Party is joined in any such action or actions. The liability of each Guarantor under this Guaranty shall be irrevocable, absolute and unconditional irrespective of, and each Guarantor hereby irrevocably waives any defenses it may now have or hereafter acquire in any way relating to, any or all of the following:

     (a) any lack of validity or enforceability of any Loan Document or any agreement or instrument relating thereto;

     (b) any change in the time, manner or place of payment of, or in any other term of, all or any of the Guaranteed Obligations or any other Obligations of any other Loan Party under or in respect of the Loan Documents, or any other amendment or waiver of or any consent to departure from any Loan Document, including, without limitation, any increase in the Guaranteed Obligations resulting from the extension of additional credit to any Loan Party or any of its Subsidiaries or otherwise;

     (c) any taking, exchange, release or non-perfection of any Collateral or any other collateral, or any taking, release or amendment or waiver of, or consent to departure from, any other guaranty, for all or any of the Guaranteed Obligations;

     (d) any manner of application of Collateral or any other collateral, or proceeds thereof, to all or any of the Guaranteed Obligations, or any manner of sale or other disposition of any Collateral or any other collateral for all or any of the Guaranteed Obligations or any other Obligations of any Loan Party under the Loan Documents or any other assets of any Loan Party or any of its Subsidiaries;

     (e) any change, restructuring or termination of the corporate structure or existence of any Loan Party or any of its Subsidiaries;

     (f) any failure of any Secured Party to disclose to any Loan Party any information relating to the business, condition (financial or otherwise), operations, performance, properties or prospects of any other Loan Party now or hereafter known to such Secured Party (each Guarantor waiving any duty on the part of the Secured Parties to disclose such information);

     (g) the failure of any other Person to execute or deliver this Guaranty, any Guaranty Supplement (as hereinafter defined) or any other guaranty or agreement or the release or reduction of liability of any Guarantor or other guarantor or surety with respect to the Guaranteed Obligations; or

     (h) any other circumstance (including, without limitation, any statute of limitations) or any existence of or reliance on any representation by any Secured Party that might otherwise constitute a defense available to, or a discharge of, any Loan Party or any other guarantor or surety.

This Guaranty shall continue to be effective or be reinstated, as the case may be, if at any time any payment of any of the Guaranteed Obligations is rescinded or must otherwise be returned by any Secured Party or any other Person upon the insolvency, bankruptcy or reorganization of the Borrower or any other Loan Party or otherwise, all as though such payment had not been made.

     Section 3. Waivers and Acknowledgments. (a) Each Guarantor hereby unconditionally and irrevocably waives promptness, diligence, notice of acceptance, presentment, demand for performance, notice of nonperformance, default, acceleration, protest or dishonor and any other notice with respect to any of the Guaranteed Obligations and this Guaranty and any requirement that any Secured Party protect, secure, perfect or insure any Lien or any property subject thereto or exhaust any right or take any action against any Loan Party or any other Person or any Collateral.

     (b) Each Guarantor hereby unconditionally and irrevocably waives any right to revoke this Guaranty and acknowledges that this Guaranty is continuing in nature and applies to all Guaranteed Obligations, whether existing now or in the future.

     (c) Each Guarantor hereby unconditionally and irrevocably waives (i) any defense arising by reason of any claim or defense based upon an election of remedies by any Secured Party that in any manner impairs, reduces, releases or otherwise adversely affects the subrogation, reimbursement, exoneration, contribution or indemnification rights of such Guarantor or other rights of such Guarantor to proceed against any of the other Loan Parties, any

other guarantor or any other Person or any Collateral and (ii) any defense based on any right of set-off or counterclaim against or in respect of the Obligations of such Guarantor hereunder.

     (d) Each Guarantor acknowledges that the Collateral Agent may, without notice to or demand upon such Guarantor and without affecting the liability of such Guarantor under this Guaranty, foreclose under any mortgage by nonjudicial sale, and each Guarantor hereby waives any defense to the recovery by the Collateral Agent and the other Secured Parties against such Guarantor of any deficiency after such nonjudicial sale and any defense or benefits that may be afforded by Sections 580a and 580d of the California Code of Civil Procedure or any statute or law in any other jurisdiction having similar effect or any other applicable law.

     (e) Each Guarantor hereby unconditionally and irrevocably waives any duty on the part of any Secured Party to disclose to such Guarantor any matter, fact or thing relating to the business, condition (financial or otherwise), operations, performance, properties or prospects of any other Loan Party or any of its Subsidiaries now or hereafter known by such Secured Party.

     (f) Each Guarantor acknowledges that it will receive substantial direct and indirect benefits from the financing arrangements contemplated by the Loan Documents and that the waivers set forth in Section 2 and this Section 3 are knowingly made in contemplation of such benefits.

     Section 4. Subrogation. Each Guarantor hereby unconditionally and irrevocably agrees not to exercise any rights that it may now have or hereafter acquire against the Borrower, any other Loan Party or any other insider guarantor that arise from the existence, payment, performance or enforcement of such Guarantor’s Obligations under or in respect of this Guaranty or any other Loan Document, including, without limitation, any right of subrogation, reimbursement, exoneration, contribution or indemnification and any right to participate in any claim or remedy of any Secured Party against the Borrower, any other Loan Party or any other insider guarantor or any Collateral, whether or not such claim, remedy or right arises in equity or under contract, statute or common law, including, without limitation, the right to take or receive from the Borrower, any other Loan Party or any other insider guarantor, directly or indirectly, in cash or other property or by set-off or in any other manner, payment or security on account of such claim, remedy or right, unless and until all of the Guaranteed Obligations and all other amounts payable under this Guaranty shall have been paid in full in cash, all Secured Hedge Agreements shall have expired or been terminated and the Term Commitments shall have expired or been terminated. If any amount shall be paid to any Guarantor in violation of the immediately preceding sentence at any time prior to the latest of (a) the payment in full in cash of the Guaranteed Obligations and all other amounts payable under this Guaranty, (b) the Scheduled Maturity Date and (c) the latest date of expiration or termination of all Secured Hedge Agreements, such amount shall be received and held in trust for the benefit of the Secured Parties, shall be segregated from other property and funds of such Guarantor and shall forthwith be paid or delivered to the Administrative Agent in the same form as so received (with any necessary endorsement or assignment) to be credited and applied to the Guaranteed Obligations and all other amounts payable under this Guaranty, whether matured or unmatured, in accordance with the terms of the Loan Documents, or to be held as Collateral for any Guaranteed Obligations or other amounts payable under this Guaranty thereafter arising. If (i) any Guarantor

shall make payment to any Secured Party of all or any part of the Guaranteed Obligations, (ii) all of the Guaranteed Obligations and all other amounts payable under this Guaranty shall have been paid in full in cash, (iii) the Scheduled Maturity Date shall have occurred and (iv) all Secured Hedge Agreements shall have expired or been terminated, the Secured Parties will, at such Guarantor’s request and expense, execute and deliver to such Guarantor appropriate documents, without recourse and without representation or warranty, necessary to evidence the transfer by subrogation to such Guarantor of an interest in the Guaranteed Obligations resulting from such payment made by such Guarantor pursuant to this Guaranty.

     Section 5. Payments Free and Clear of Taxes, Etc. Any and all payments by or on account of any obligation of any Guarantor hereunder or under any other Loan Document shall be made free and clear of and without deduction or withholding for any Indemnified Taxes or Other Taxes on the same terms and to the same extent that payments by the Borrower are required to be made free and clear of Indemnified Taxes and Other Taxes pursuant to Section 3.01 of the Credit Agreement.

     Section 6. Representations and Warranties. Each Guarantor hereby makes each representation and warranty made in the Loan Documents by the Borrower with respect to such Guarantor and each Guarantor hereby further represents and warrants as follows:

     (a) There are no conditions precedent to the effectiveness of this Guaranty that have not been satisfied or waived.

     (b) Such Guarantor has, independently and without reliance upon any Secured Party and based on such documents and information as it has deemed appropriate, made its own credit analysis and decision to enter into this Guaranty and each other Loan Document to which it is or is to be a party, and such Guarantor has established adequate means of obtaining from each other Loan Party on a continuing basis information pertaining to, and is now and on a continuing basis will be completely familiar with, the business, condition (financial or otherwise), operations, performance, properties and prospects of such other Loan Party.

     Section 7. Covenants. Each Guarantor covenants and agrees that, so long as any part of the Guaranteed Obligations (other than Unaccrued Indemnity Claims) shall remain unpaid, any Lender shall have any Term Commitment or any Secured Hedge Agreement shall be in effect, such Guarantor will perform and observe, and cause each of its Subsidiaries to perform and observe, all of the terms, covenants and agreements set forth in the Loan Documents on such Guarantor’s or its Subsidiaries’ part to be performed or observed or that the Borrower has agreed to cause such Guarantor or such Subsidiaries to perform or observe.

     Section 8. Amendments, Guaranty Supplements, Etc. (a) No amendment or waiver of any provision of this Guaranty and no consent to any departure by any Guarantor therefrom shall in any event be effective unless the same shall be in writing and signed by the Administrative Agent and the Required Lenders (or signed by the Administrative Agent with the consent of the Required Lenders) and, in the case of an amendment, the Guarantors, and then such waiver or consent shall be effective only in the specific instance and for the specific purpose for which given; provided, however, that no amendment, waiver or consent shall, unless

in writing and signed by all of the Lenders (or signed by the Administrative Agent with the consent of all the Lenders) (other than any Lender that is, at such time, a Defaulting Lender), (i) release all or substantially all the value under this Guaranty, or (ii) change this Section 8. Upon the sale of a Guarantor to a Person other than a Loan Party or a Subsidiary of a Loan Party to the extent permitted in accordance with the terms of the Loan Documents, such Guarantor shall be automatically released from this Guaranty without the requirement of any further action on the part of the Lenders or any Agent.

     (b) Upon the execution and delivery by any Person of a guaranty supplement in substantially the form of Exhibit A hereto (each, a “Guaranty Supplement”), (i) such Person shall be referred to as an “Additional Guarantor” and shall become and be a Guarantor hereunder, and each reference in this Guaranty to a “Guarantor” shall also mean and be a reference to such Additional Guarantor, and each reference in any other Loan Document to a “Subsidiary Guarantor” shall also mean and be a reference to such Additional Guarantor, and (ii) each reference herein to “this Guaranty”, “hereunder”, “hereof” or words of like import referring to this Guaranty, and each reference in any other Loan Document to the “Subsidiary Guaranty”, “thereunder”, “thereof” or words of like import referring to this Guaranty, shall mean and be a reference to this Guaranty as supplemented by such Guaranty Supplement.

     Section 9. Notices, Etc. All notices and other communications provided for hereunder shall be in writing (including telegraphic, telecopy or telex communication) and mailed, telegraphed, telecopied, telexed or delivered, if to any Guarantor, in care of the Borrower at the Borrower’s address specified in Section 10.02 of the Credit Agreement, if to any Agent or any Lender, at its address specified in Section 10.02 of the Credit Agreement, if to any Hedge Bank, at its address specified in the Secured Hedge Agreement to which it is a party, or, as to any party, at such other address as shall be designated by such party in a written notice to each other party. All such notices and other communications shall, when mailed, telegraphed, telecopied or telexed, be effective when deposited in the mails, delivered to the telegraph company, transmitted by telecopier or confirmed by telex answerback, respectively. Delivery by telecopier of an executed counterpart of a signature page to any amendment or waiver of any provision of this Guaranty or of any Guaranty Supplement to be executed and delivered hereunder shall be effective as delivery of an original executed counterpart thereof.

     Section 10. No Waiver; Remedies. No failure on the part of any Secured Party to exercise, and no delay by any Secured Party in exercising, any right, remedy, power or privilege hereunder shall operate as a waiver thereof; nor shall any single or partial exercise of any right, remedy, power or privilege hereunder preclude any other or further exercise thereof or the exercise of any other right, remedy, power or privilege. The rights, remedies, powers and privileges herein provided are cumulative and not exclusive of any rights, remedies, powers and privileges provided by law.

     Section 11. Right of Set-off. Upon (a) the occurrence and during the continuance of an Event of Default under Section 8.01(a) of the Credit Agreement, (b) an exercise or remedies under Section 8.02(b) of the Credit Agreement or (c) amounts becoming due and payable pursuant to the proviso to Section 8.02 of the Credit Agreement, each Agent and each Lender and each of their respective Affiliates is hereby authorized at any time and from time to time, to the fullest extent permitted by law, to set off and apply any and all deposits (general or

special, time or demand, provisional or final) at any time held and other indebtedness at any time owing by such Agent, such Lender or such Affiliate to or for the credit or the account of any Guarantor against any and all of the Obligations of such Guarantor now or hereafter existing under the Loan Documents, irrespective of whether such Agent or such Lender shall have made any demand under this Guaranty or any other Loan Document and although such Obligations may be unmatured. Each Agent and each Lender agrees promptly to notify such Guarantor after any such set-off and application; provided, however, that the failure to give such notice shall not affect the validity of such set-off and application. The rights of each Agent and each Lender and their respective Affiliates under this Section 11 are in addition to other rights and remedies (including, without limitation, other rights of set-off) that such Agent, such Lender and their respective Affiliates may have.

     Section 12. Indemnification. (a) Without limitation on any other Obligations of any Guarantor or remedies of the Secured Parties under this Guaranty, each Guarantor shall, to the fullest extent permitted by law, indemnify, defend and save and hold harmless each Secured Party and each Related Party (each, an “Indemnified Party”) from and against, and shall pay on demand, any and all claims, damages, losses, liabilities and expenses (including, without limitation, reasonable fees and expenses of counsel) that may be incurred by or asserted or awarded against any Indemnified Party in connection with or as a result of any failure of any Guaranteed Obligations to be the legal, valid and binding obligations of any Loan Party enforceable against such Loan Party in accordance with their terms.

     (b) Each Guarantor hereby also agrees that none of the Indemnified Parties shall have any liability (whether direct or indirect, in contract, tort or otherwise) to any of the Guarantors or any Related Parties, and each Guarantor hereby agrees not to assert any claim against any Indemnified Party on any theory of liability, for special, indirect, consequential or punitive damages arising out of or otherwise relating to the Facilities, the actual or proposed use of the proceeds of the Term Loans, the Transaction Documents or any of the transactions contemplated by the Transaction Documents.

     (c) Without prejudice to the survival of any of the other agreements of any Guarantor under this Guaranty or any of the other Loan Documents, the agreements and obligations of each Guarantor contained in Section 1(a) (with respect to enforcement expenses), the last sentence of Section 2, Section 5 and this Section 12 shall survive the payment in full of the Guaranteed Obligations and all of the other amounts payable under this Guaranty until the expiration of any applicable statute of limitations.

     Section 13. Subordination. Each Guarantor hereby subordinates any and all debts, liabilities and other Obligations owed to such Guarantor by each other Loan Party (the “Subordinated Obligations”) to the Guaranteed Obligations to the extent and in the manner hereinafter set forth in this Section 13:

     (a) Prohibited Payments, Etc. Except during the continuance of an Event of Default or a Default (each, a “Specified Default”) under Section 8.01(a), (f) or (g) of the Credit Agreement, each Guarantor may receive regularly scheduled payments from any other Loan Party on account of the Subordinated Obligations. After the occurrence and during the continuance of any Event of Default or Specified Default, however, unless the Administrative Agent otherwise agrees, no Guarantor shall demand, accept or take any action to collect any payment on account of the Subordinated Obligations.

     (b) Prior Payment of Guaranteed Obligations. In any proceeding under any Bankruptcy Law relating to any other Loan Party, each Guarantor agrees that the Secured Parties shall be entitled to receive payment in full in cash of all Guaranteed Obligations (including all interest and expenses accruing after the commencement of a proceeding under any Bankruptcy Law, whether or not constituting an allowed claim in such proceeding (“Post Petition Interest”)) before such Guarantor receives payment of any Subordinated Obligations.

     (c) Turn-Over. Upon the occurrence and during the continuance of any Event of Default or Specified Default, each Guarantor shall, if the Administrative Agent so requests, collect, enforce and receive payments on account of the Subordinated Obligations as trustee for the Secured Parties and deliver such payments to the Administrative Agent on account of the Guaranteed Obligations (including all Post Petition Interest), together with any necessary endorsements or other instruments of transfer, but without reducing or affecting in any manner the liability of such Guarantor under the other provisions of this Guaranty.

     (d) Administrative Agent Authorization. Upon (a) the occurrence and during the continuance of an Event of Default or Specified Default, the Administrative Agent is authorized and empowered (but without any obligation to so do), in its discretion, (i) in the name of each Guarantor, to collect and enforce, and to submit claims in respect of, Subordinated Obligations and to apply any amounts received thereon to the Guaranteed Obligations (including any and all Post Petition Interest), and (ii) to require each Guarantor (A) to collect and enforce, and to submit claims in respect of, Subordinated Obligations and (B) to pay any amounts received on such obligations to the Administrative Agent for application to the Guaranteed Obligations (including any and all Post Petition Interest).

     Section 14. Continuing Guaranty; Assignments under the Credit Agreement. This Guaranty is a continuing guaranty and shall (a) remain in full force and effect until the latest of (i) the payment in full in cash of the Guaranteed Obligations and all other amounts payable under this Guaranty, (ii) the Scheduled Maturity Date and (iii) the latest date of expiration or termination of all Secured Hedge Agreements, (b) be binding upon each Guarantor, its successors and permitted assigns and (c) inure to the benefit of and be enforceable by the Secured Parties and their successors, permitted transferees and permitted assigns. Without limiting the generality of clause (c) of the immediately preceding sentence, any Secured Party may assign or otherwise transfer all or any portion of its rights and obligations under the Credit Agreement (including, without limitation, all or any portion of its Term Commitments, the Term Loans owing to it and the Note or Notes held by it) to any other Person, and such other Person shall thereupon become vested with all the benefits in respect thereof granted to such Secured Party herein or otherwise, in each case as and to the extent provided in Section 10.06 of the Credit Agreement. No Guarantor shall have the right to assign its rights hereunder or any interest herein without the prior written consent of the Secured Parties.

     Section 15. Execution in Counterparts. This Guaranty and each amendment, waiver and consent with respect hereto may be executed in any number of counterparts and by different parties thereto in separate counterparts, each of which when so executed shall be deemed to be an original and all of which taken together shall constitute one and the same agreement. Delivery by telecopier or in .pdf or similar format by electronic mail of an executed counterpart of a signature page to this Guaranty or any amendment or waiver of any provision of the Guaranty or of any Guaranty Supplement to be executed and delivered hereunder shall be effective as delivery of an original executed counterpart of this Guaranty hereof and thereof.

     Section 16. Governing Law; Jurisdiction; Waiver of Jury Trial, Etc. (a) This Guaranty shall be governed by, and construed in accordance with, the laws of the State of New York.

     (b) EACH GUARANTOR HEREBY IRREVOCABLY AND UNCONDITIONALLY SUBMITS, FOR ITSELF AND ITS PROPERTY, TO THE NONEXCLUSIVE JURISDICTION OF ANY NEW YORK STATE COURT OR FEDERAL COURT OF THE UNITED STATES OF AMERICA SITTING IN NEW YORK CITY, AND ANY APPELLATE COURT FROM ANY THEREOF (COLLECTIVELY, “NEW YORK COURTS”), IN ANY ACTION OR PROCEEDING ARISING OUT OF OR RELATING TO THIS GUARANTY OR ANY OF THE OTHER LOAN DOCUMENTS TO WHICH IT IS A PARTY, OR FOR RECOGNITION OR ENFORCEMENT OF ANY JUDGMENT, AND EACH OF THE PARTIES HERETO HEREBY IRREVOCABLY AND UNCONDITIONALLY AGREES THAT ALL CLAIMS IN RESPECT OF ANY SUCH ACTION OR PROCEEDING MAY BE HEARD AND DETERMINED IN ANY SUCH NEW YORK STATE COURT OR, TO THE FULLEST EXTENT PERMITTED BY LAW, IN SUCH FEDERAL COURT. EACH OF THE PARTIES HERETO AGREES THAT A FINAL JUDGMENT IN ANY SUCH ACTION OR PROCEEDING SHALL BE CONCLUSIVE AND MAY BE ENFORCED IN OTHER JURISDICTIONS BY SUIT ON THE JUDGMENT OR IN ANY OTHER MANNER PROVIDED BY LAW. NOTHING IN THIS AGREEMENT SHALL AFFECT ANY RIGHT THAT THE AGENTS OR ANY LENDER MAY OTHERWISE HAVE TO

BRING ANY ACTION OR PROCEEDING RELATING TO THIS GUARANTY OR ANY OF THE OTHER LOAN DOCUMENTS IN THE COURTS OF ANY JURISDICTION, except that each of the Guarantors agrees that (i) it will not bring any such action or proceeding in any court other than New York Courts (it being acknowledged and agreed by the parties hereto that any other forum would be inconvenient and inappropriate in view of the fact that more of the Lenders who would be affected by any such action or proceeding have contacts with the State of New York than any other jurisdiction), and (ii) in any such action or proceeding brought against any Guarantor in any other court, it will not assert any cross-claim, counterclaim or setoff, or seek any other affirmative relief, except to the extent that the failure to assert the same will preclude such Guarantor from asserting or seeking the same in the New York Courts.

     (c) Each Guarantor irrevocably and unconditionally waives, to the fullest extent it may legally and effectively do so, any objection that it may now or hereafter have to the laying of venue of any suit, action or proceeding arising out of or relating to this Guaranty or any of the other Loan Documents to which it is or is to be a party in any New York State or federal court. Each Guarantor hereby irrevocably waives, to the fullest extent permitted by law, the defense of an inconvenient forum to the maintenance of such suit, action or proceeding in any such court.

     (d) EACH GUARANTOR HEREBY IRREVOCABLY WAIVES ALL RIGHT TO TRIAL BY JURY IN ANY ACTION, PROCEEDING OR COUNTERCLAIM (WHETHER BASED ON CONTRACT, TORT OR OTHERWISE) ARISING OUT OF OR RELATING TO ANY OF THE LOAN DOCUMENTS, THE TERM LOANS OR THE ACTIONS OF ANY SECURED PARTY IN THE NEGOTIATION, ADMINISTRATION, PERFORMANCE OR ENFORCEMENT THEREOF.

[Signature Page to Follow]

     IN WITNESS WHEREOF, each Grantor has caused this Agreement to be duly executed and delivered by its officer thereunto duly authorized as of the date first above written.

		Address for notices:
		2601 S. Bayshore Drive
		Suite 900
		Miami, FL 33133

		Address for notices:
		2601 S. Bayshore Drive
		Suite 900
		Miami, FL 33133

		Address for notices:
		2601 S. Bayshore Drive
		Suite 900
		Miami, FL 33133

 

Terremark — First Lien Subsidiary Guaranty

		Address for notices:
		2601 S. Bayshore Drive
		Suite 900
		Miami, FL 33133

		Address for notices:
		2601 S. Bayshore Drive
		Suite 900
		Miami, FL 33133

		Address for notices:
		2601 S. Bayshore Drive
		Suite 900
		Miami, FL 33133

		Address for notices:
		2601 S. Bayshore Drive
		Suite 900
		Miami, FL 33133

		Address for notices:
		2601 S. Bayshore Drive
		Suite 900
		Miami, FL 33133

		Address for notices:
		2601 S. Bayshore Drive
		Suite 900
		Miami, FL 33133

		Address for notices:
		2601 S. Bayshore Drive
		Suite 900
		Miami, FL 33133

		Address for notices:
		2601 S. Bayshore Drive
		Suite 900
		Miami, FL 33133

		Address for notices:
		2601 S. Bayshore Drive
		Suite 900
		Miami, FL 33133

		Address for notices:
		2601 S. Bayshore Drive
		Suite 900
		Miami, FL 33133

		Address for notices:
		2601 S. Bayshore Drive
		Suite 900
		Miami, FL 33133

		Address for notices:
		2601 S. Bayshore Drive
		Suite 900
		Miami, FL 33133

		Address for notices:
		2601 S. Bayshore Drive
		Suite 900
		Miami, FL 33133

		Address for notices:
		2601 S. Bayshore Drive
		Suite 900
		Miami, FL 33133

		Address for notices:
		2601 S. Bayshore Drive
		Suite 900
		Miami, FL 33133

		Address for notices:
		2601 S. Bayshore Drive
		Suite 900
		Miami, FL 33133

		Address for notices:
		222 West Las Colinas Blvd.
		Suite 350-E
		Irving, TX 75039

		Address for notices:
		222 West Las Colinas Blvd.
		Suite 350-E
		Irving, TX 75039

Exhibit A
To The
Subsidiary Guaranty

FORM OF SUBSIDIARY GUARANTY SUPPLEMENT

[___________], [____]

Credit Suisse, as Administrative Agent
[Address of Administrative Agent]

Attention: _________

Terremark Worldwide, Inc.,
First Lien Senior Secured Credit Agreement dated as of July 31, 2007

Ladies and Gentlemen:

     We refer to (i) the First Lien Senior Secured Credit Agreement dated as of July 31, 2007 among Terremark Worldwide, Inc., a Delaware corporation, the Lenders party thereto, and Credit Suisse, acting through one or more of its branches (“Credit Suisse”), as Administrative Agent and Collateral Agent, and (ii) the Subsidiary Guaranty referred to therein (such Subsidiary Guaranty, as in effect on the date hereof and as it may hereafter be amended, supplemented or otherwise modified from time to time, together with this Guaranty Supplement, being the “Subsidiary Guaranty”). The capitalized terms defined in the Subsidiary Guaranty or in the Credit Agreement and not otherwise defined herein are used herein as therein defined

Section 1. Guaranty; Limitation of Liability. (a) The undersigned hereby absolutely, unconditionally and irrevocably guarantees the punctual payment when due, whether at scheduled maturity or on any date of a required prepayment or by acceleration, demand or otherwise, of all Obligations of each other Loan Party now or hereafter existing under or in respect of the Loan Documents (including, without limitation, any extensions, modifications, substitutions, amendments or renewals of any or all of the foregoing Obligations), whether direct or indirect, absolute or contingent, and whether for principal, interest, premium, fees, indemnities, contract causes of action, costs, expenses or otherwise (such Obligations being the “Guaranteed Obligations”), and agrees to pay any and all expenses (including, without limitation, fees and expenses of counsel) incurred by the Administrative Agent or any other Secured Party in enforcing any rights under this Guaranty Supplement, the Subsidiary Guaranty or any other Loan Document. Without limiting the generality of the foregoing, the undersigned’s liability shall extend to all amounts that constitute part of the Guaranteed Obligations and would be owed by any other Loan Party to any Secured Party under or in respect of the Loan Documents but for the fact that they are unenforceable or not allowable due to the existence of a bankruptcy, reorganization or similar proceeding involving such other Loan Party.

     (b) The undersigned, and by its acceptance of this Guaranty Supplement, the Administrative Agent and each other Secured Party, hereby confirms that it is the intention of all such Persons that this Guaranty Supplement, the Subsidiary Guaranty and the Obligations of the

undersigned hereunder and thereunder not constitute a fraudulent transfer or conveyance for purposes of Bankruptcy Law, the Uniform Fraudulent Conveyance Act, the Uniform Fraudulent Transfer Act or any similar foreign, federal or state law to the extent applicable to this Guaranty Supplement, the Subsidiary Guaranty and the Obligations of the undersigned hereunder and thereunder. To effectuate the foregoing intention, the Administrative Agent, the other Secured Parties and the undersigned hereby irrevocably agree that the Obligations of the undersigned under this Guaranty Supplement and the Subsidiary Guaranty at any time shall be limited to the maximum amount as will result in the Obligations of the undersigned under this Guaranty Supplement and the Subsidiary Guaranty not constituting a fraudulent transfer or conveyance.

     (c) The undersigned hereby unconditionally and irrevocably agrees that in the event any payment shall be required to be made to any Secured Party under this Guaranty Supplement, the Subsidiary Guaranty, or any other guaranty, the undersigned will contribute, to the maximum extent permitted by applicable law, such amounts to each other Guarantor and each other guarantor so as to maximize the aggregate amount paid to the Secured Parties under or in respect of the Loan Documents.

     Section 2. Obligations Under the Guaranty. The undersigned hereby agrees, as of the date first above written, to be bound as a Guarantor by all of the terms and conditions of the Subsidiary Guaranty to the same extent as each of the other Guarantors thereunder. The undersigned further agrees, as of the date first above written, that each reference in the Subsidiary Guaranty to an “Additional Guarantor” or a “Guarantor” shall also mean and be a reference to the undersigned, and each reference in any other Loan Document to a “Subsidiary Guarantor” or a “Loan Party” shall also mean and be a reference to the undersigned.

     Section 3. Representations and Warranties. The undersigned hereby makes each representation and warranty set forth in Section 6 of the Subsidiary Guaranty (subject to any corresponding disclosure schedules provided herewith, as approved by the Administrative Agent) to the same extent as each other Guarantor.

     Section 4. Delivery by Telecopier. Delivery of an executed counterpart of a signature page to this Guaranty Supplement by telecopier or in .pdf or similar format by electronic mail shall be effective as delivery of an original executed counterpart of this Guaranty Supplement.

     Section 5. Governing Law; Jurisdiction; Waiver of Jury Trial, Etc. (a) This Guaranty Supplement shall be governed by, and construed in accordance with, the laws of the State of New York.

     (b) THE UNDERSIGNED HEREBY IRREVOCABLY AND UNCONDITIONALLY SUBMITS, FOR ITSELF AND ITS PROPERTY, TO THE NONEXCLUSIVE JURISDICTION OF ANY NEW YORK COURT IN ANY ACTION OR PROCEEDING ARISING OUT OF OR RELATING TO THIS GUARANTY SUPPLEMENT OR ANY OF THE OTHER LOAN DOCUMENTS TO WHICH IT IS A PARTY, OR FOR RECOGNITION OR ENFORCEMENT OF ANY JUDGMENT, AND EACH OF THE PARTIES HERETO HEREBY IRREVOCABLY AND UNCONDITIONALLY AGREES THAT ALL CLAIMS IN RESPECT OF ANY SUCH

ACTION OR PROCEEDING MAY BE HEARD AND DETERMINED IN ANY SUCH NEW YORK COURT. EACH OF THE PARTIES HERETO AGREES THAT A FINAL JUDGMENT IN ANY SUCH ACTION OR PROCEEDING SHALL BE CONCLUSIVE AND MAY BE ENFORCED IN OTHER JURISDICTIONS BY SUIT ON THE JUDGMENT OR IN ANY OTHER MANNER PROVIDED BY LAW. NOTHING IN THIS AGREEMENT SHALL AFFECT ANY RIGHT THAT THE AGENTS OR ANY LENDER MAY OTHERWISE HAVE TO BRING ANY ACTION OR PROCEEDING RELATING TO THIS GUARANTY SUPPLEMENT OR ANY OF THE OTHER LOAN DOCUMENTS IN THE COURTS OF ANY JURISDICTION, except that the undersigned agrees that (i) it will not bring any such action or proceeding in any court other than New York Courts (it being acknowledged and agreed by the parties hereto that any other forum would be inconvenient and inappropriate in view of the fact that more of the Lenders who would be affected by any such action or proceeding have contacts with the State of New York than any other jurisdiction), and (ii) in any such action or proceeding brought against the undersigned in any other court, it will not assert any cross-claim, counterclaim or setoff, or seek any other affirmative relief, except to the extent that the failure to assert the same will preclude the undersigned from asserting or seeking the same in the New York Courts.

     (c) The undersigned irrevocably and unconditionally waives, to the fullest extent it may legally and effectively do so, any objection that it may now or hereafter have to the laying of venue of any suit, action or proceeding arising out of or relating to this Guaranty Supplement, the Subsidiary Guaranty or any of the other Loan Documents to which it is or is to be a party in any New York State or federal court. The undersigned hereby irrevocably waives, to the fullest extent permitted by law, the defense of an inconvenient forum to the maintenance of such suit, action or proceeding in any such court.

     (d) THE UNDERSIGNED HEREBY IRREVOCABLY WAIVES ALL RIGHT TO TRIAL BY JURY IN ANY ACTION, PROCEEDING OR COUNTERCLAIM (WHETHER BASED ON CONTRACT, TORT OR OTHERWISE) ARISING OUT OF OR RELATING TO ANY OF THE LOAN DOCUMENTS, THE TERM LOANS OR THE ACTIONS OF ANY SECURED PARTY IN THE NEGOTIATION, ADMINISTRATION, PERFORMANCE OR ENFORCEMENT THEREOF.