K BANK COMMERCIAL GUARANTY

Exhibit 10.15

K    BANK

COMMERCIAL GUARANTY

AMOUNT OF GUARANTY. This is a guaranty of payment of the Note, including without limitation the principal Note amount of Seven Hundred Thousand & 00/100 Dollars ($700,000.00).

GUARANTY. For good and valuable consideration, William James Hindman (“Guarantor”) absolutely and unconditionally guarantees and promises to pay to K Bank (“Lender”) or its order, in legal tender of the United States of America, the Indebtedness (as that term is defined below) of Avatech Solutions Subsidiary, Inc. (“Borrower”) to Lender on the terms and conditions set forth in this Guaranty.

MAXIMUM LIABILITY. The maximum liability of Guarantor under this Guaranty shall not exceed at any one time the amount of the Indebtedness described herein, plus all costs and expenses of (A) enforcement of this Guaranty and (B) collection and sale of any collateral securing this Guaranty.

The above limitation on liability is not a restriction on the amount of the Indebtedness of Borrower to Lender either in the aggregate or at any one time. If Lender presently holds one or more guaranties, or hereafter receives additional guaranties from Guarantor, Lender’s rights under all guaranties shall be cumulative. This Guaranty shall not (unless specifically provided below to the contrary) affect or invalidate any such other guaranties. Guarantor’s liability will be Guarantor’s aggregate liability under the terms of this Guaranty and any such other unterminated guaranties.

INDEBTEDNESS GUARANTEED. The Indebtedness guaranteed by this Guaranty includes the Note, including (a) all principal, (b) all interest, (c) all late charges, (d) all loan fees and loan charges, and (e) all collection costs and expenses relating to the Note or to any collateral for the Note. Collection costs and expenses include without limitation all of Lender’s attorneys’ fees.

DURATION OF GUARANTY. This Guaranty will take effect when received by Lender without the necessity of any acceptance by Lender, or any notice to Guarantor or to Borrower, and will continue in full force until all Indebtedness shall have been fully and finally paid and satisfied and all of Guarantor’s other obligations under this Guaranty shall have been performed in full. Release of any other guarantor or termination of any other guaranty of the Indebtedness shall not affect the liability of Guarantor under this Guaranty. A revocation Lender receives from any one or more Guarantors shall not affect the liability of any remaining Guarantors under this Guaranty. This Guaranty covers a revolving line of credit and it is specifically anticipated that fluctuations will occur in the aggregate amount of Indebtedness owing from Borrower to Lender. Guarantor specifically acknowledges and agrees that fluctuations in the amount of Indebtedness, even to zero dollars ($ 0.00), shall not constitute a termination of this Guaranty. Guarantor’s liability under this Guaranty shall terminate only upon (A) termination in writing by Borrower and Lender of the line of credit, (B) payment of the Indebtedness in full in legal tender, and (C) payment in full in legal tender of all of Guarantor’s other obligations under this Guaranty.

GUARANTOR’S AUTHORIZATION TO LENDER. Guarantor authorizes Lender, without notice or demand and without lessening Guarantor’s liability under this Guaranty, from time to time: (A) to make one or more additional secured or unsecured loans to Borrower, to lease equipment or other goods to Borrower, or otherwise to extend additional credit to Borrower; (B) to alter, compromise, renew, extend, accelerate, or otherwise change one or more times the time for payment or other terms of the Indebtedness or any part of the Indebtedness, including increases and decreases of the rate of interest on the Indebtedness; (C) to take and hold security for the payment of this Guaranty or the Indebtedness, and exchange, enforce, waive, subordinate, fail or decide not to perfect, and release any such security, with or without the substitution of new collateral; (D) to release, substitute, agree not to sue, or deal with any one or more of Borrower’s sureties, endorsers, or other guarantors on any terms or in any manner Lender may choose; (E) to determine how, when and what application of payments and credits shall be made on the Indebtedness (F) to apply such security and direct the order or manner of sale thereof, including without limitation, any nonjudicial sale permitted by the terms of the controlling security agreement or deed of trust, as Lender in its discretion may determine; (G) to sell, transfer, assign or grant participations in all or any part of the Indebtedness; and (H) to assign or transfer this Guaranty in whole or in part.

GUARANTOR’S REPRESENTATIONS AND WARRANTIES. Guarantor represents and warrants to Lender that (A) no representations or agreements of any kind have been made to Guarantor which would limit or qualify in any way the terms of this Guaranty; (B) this Guaranty is executed at Borrower’s request and not at the request of Lender; (C) Guarantor has full power, right and authority to enter into this Guaranty; (D) the provisions of this Guaranty do not conflict with or result in a default under any agreement or other instrument binding upon Guarantor and do not result in a violation of any law, regulation, court decree or order applicable to Guarantor; (E) Guarantor has not and will not, without the prior written consent of Lender, sell, lease, assign, encumber, hypothecate, transfer, or otherwise dispose of all or substantially all of Guarantor’s assets, or any interest therein; (F) upon Lender’s request, Guarantor will provide to Lender financial and credit information in form acceptable to Lender, and all such financial information which currently has been, and all future financial information which will be provided to Lender is and will be true and correct in all material respects and fairly present Guarantor’s financial condition as of the dates the financial information is provided; (G) no material adverse change has occurred in Guarantor’s financial condition since the date of the most recent financial statements provided to Lender and no event has occurred which may materially adversely affect Guarantor’s financial condition; (H) no litigation, claim, investigation, administrative proceeding or similar action (including those for unpaid taxes) against Guarantor is pending or threatened; (I) Lender has made no representation to Guarantor as to the creditworthiness of Borrower; and (J) Guarantor has established adequate means of obtaining from Borrower on a continuing basis information regarding Borrower’s financial condition. Guarantor agrees to keep adequately informed from such means of any facts, events, or circumstances which might in any way affect Guarantor’s risks under this Guaranty, and Guarantor further agrees that, absent a request for information, Lender shall have no obligation to disclose to Guarantor any information or documents acquired by Lender in the course of its relationship with Borrower.

GUARANTOR’S FINANCIAL STATEMENTS. Guarantor agrees to furnish Lender with the following:

Annual Statements. As soon as available, but in no event later than one-hundred-twenty (120) days after the end of each fiscal year, Guarantor’s balance sheet and income statement for the year ended, prepared by Guarantor.

Tax Returns. As soon as available, but in no event later than thirty (30) days after the applicable filing date for the tax reporting period ended, Federal and other governmental tax returns, prepared by a certified public accountant satisfactory to Lender.

All financial reports required to be provided under this Guaranty shall be prepared in accordance with GAAP, applied on a consistent basis, and certified by Guarantor as being true and correct.

GUARANTOR’S WAIVERS. Except as prohibited by applicable law, Guarantor waives any right to require Lender (A) to continue lending money or to extend other credit to Borrower; (B) to make any presentment, protest, demand, or notice of any kind, including notice of any nonpayment of the Indebtedness or of any nonpayment related to any collateral, or notice of any action or nonaction on the part of Borrower, Lender, any surety, endorser, or other guarantor in connection with the Indebtedness or in connection with the creation of new or additional loans or obligations; (C) to resort for payment or to proceed directly or at once against any person, including Borrower or any other guarantor; (D) to proceed directly against or exhaust any collateral held by Lender from Borrower, any other guarantor, or any other person; (E) to give notice of the terms, time, and place of any public or private sale of personal property security held by Lender from Borrower or to comply with any other applicable provisions of the Uniform Commercial Code; (F) to pursue any other remedy within Lender’s power; or (G) to commit any act or omission of any kind, or at any time, with respect to any matter whatsoever.

In addition to the waivers set forth herein, if now or hereafter Borrower is or shall become insolvent and the Indebtedness shall not at all times until paid be fully secured by collateral pledged by Borrower, Guarantor hereby forever waives and gives up in favor of Lender and Borrower, and Lender’s and Borrower’s respective successors, any claim or right to payment Guarantor may now have or hereafter have or acquire against Borrower, by subrogation or otherwise, so that at no time shall Guarantor be or become a “creditor” of Borrower within the meaning of 11 U.S.C. section 547(b), or any successor provision of the Federal bankruptcy laws.

Guarantor also waives any and all rights or defenses arising by reason of (1) any election of remedies by Lender which destroys or otherwise adversely affects Guarantor’s subrogation rights or Guarantor’s rights to proceed against Borrower for reimbursement, including without limitation, any loss of rights Guarantor may suffer by reason of any law limiting, qualifying, or discharging the Indebtedness; (2) any disability or other defense of Borrower, of any other guarantor, or of any other person, or by reason of the cessation of Borrower’s liability from any cause whatsoever, other than payment in full in legal tender, of the Indebtedness; (3) any right to claim discharge of the Indebtedness on the basis of unjustified impairment of any Collateral for the Indebtedness; or (4) any statute of limitations, if at any time any action or suit brought by Lender against Guarantor is commenced,

COMMERCIAL GUARANTY

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Loan No: 220583814

there is outstanding Indebtedness of Borrower to Lender which is not barred by any applicable statute of limitations. Guarantor acknowledges and agrees that Guarantor’s obligations under this Guaranty shall apply to and continue with respect to any amount paid to Lender which is subsequently recovered from Lender for any reason whatsoever (including without limitation as a result of bankruptcy, insolvency or fraudulent conveyance proceeding), notwithstanding the fact that all or a part of the Indebtedness may have been previously paid, or this Guaranty may have been terminated, or both.

Guarantor further waives and agrees not to assert or claim at any time any deductions to the amount guaranteed under this Guaranty for any claim of setoff, counterclaim, counter demand, recoupment or similar right, whether such claim, demand or right may be asserted by the Borrower, the Guarantor, or both.

Guarantor’s Understanding With Respect To Waivers. Guarantor warrants and agrees that each of the waivers set forth above is made with Guarantor’s full knowledge of its significance and consequences and that, under the circumstances, the waivers are reasonable and not contrary to public policy or law. If any such waiver is determined to be contrary to any applicable law or public policy, such waiver shall be effective only to the extent permitted by law or public policy.

Right of Setoff. To the extent permitted by applicable law, Lender reserves a right of setoff in all Guarantor’s accounts with Lender (whether checking, savings, or some other account). This includes all accounts Guarantor holds jointly with someone else and all accounts Guarantor may open in the future. However, this does not include any IRA or Keogh accounts, or any trust accounts for which setoff would be prohibited by law. Guarantor authorizes Lender, to the extent permitted by applicable law, to hold these funds if there is a default, and Lender may apply the funds in these accounts to pay what Guarantor owes under the terms of this Guaranty.

Subordination of Borrower’s Debts to Guarantor. Guarantor agrees that the Indebtedness of Borrower to Lender, whether now existing or hereafter created, shall be superior to any claim that Guarantor may now have or hereafter acquire against Borrower, whether or not Borrower becomes insolvent. Guarantor hereby expressly subordinates any claim Guarantor may have against Borrower, upon any account whatsoever, to any claim that Lender may now or hereafter have against Borrower. In the event of insolvency and consequent liquidation of the assets of Borrower, through bankruptcy, by an assignment for the benefit of creditors, by voluntary liquidation, or otherwise, the assets of Borrower applicable to the payment of the claims of both Lender and Guarantor shall be paid to Lender and shall be first applied by Lender to the Indebtedness of Borrower to Lender. Guarantor does hereby assign to Lender all claims which it may have or acquire against Borrower or against any assignee or trustee in bankruptcy of Borrower; provided however, that such assignment shall be effective only for the purpose of assuring to Lender full payment in legal tender of the Indebtedness. If Lender so requests, any notes or credit agreements now or hereafter evidencing any debts or obligations of Borrower to Guarantor shall be marked with a legend that the same are subject to this Guaranty and shall be delivered to Lender. Guarantor agrees, and Lender is hereby authorized, in the name of Guarantor, from time to time to file financing statements and continuation statements and to execute documents and to take such other actions as Lender deems necessary or appropriate to perfect, preserve and enforce its rights under this Guaranty.

CONFESSED JUDGMENT. UPON THE OCCURRENCE OF A DEFAULT ON THE INDEBTEDNESS, GUARANTOR HEREBY AUTHORIZES ANY ATTORNEY DESIGNATED BY LENDER OR ANY CLERK OF ANY COURT OF RECORD TO APPEAR FOR GUARANTOR IN ANY COURT OF RECORD AND CONFESS JUDGMENT WITHOUT PRIOR HEARING AGAINST GUARANTOR IN FAVOR OF LENDER FOR, AND IN THE AMOUNT OF, THE UNPAID BALANCE OF THE PRINCIPAL AMOUNT OF THIS GUARANTY, ALL INTEREST ACCRUED AND UNPAID THEREON, ALL OTHER AMOUNTS PAYABLE BY GUARANTOR TO LENDER UNDER THE TERMS OF THIS GUARANTY OR ANY OTHER AGREEMENT, DOCUMENTS, INSTRUMENT EVIDENCING, SECURING OR GUARANTYING THE OBLIGATIONS EVIDENCED BY THIS GUARANTY, COSTS OF SUIT, AND ATTORNEYS’ FEES OF FIFTEEN PERCENT (15%) OF THE UNPAID BALANCE OF THE PRINCIPAL AMOUNT OF THIS GUARANTY AND INTEREST THEN DUE HEREUNDER.

Guarantor hereby releases, to the extent permitted by applicable law, all errors and all rights of exemption, appeal, stay of execution, inquisition, and other rights to which Borrower may otherwise be entitled under the laws of the United States or of any state or possession of the United States now in force and which may hereafter be enacted. The authority and power to appear for and enter judgment against Guarantor shall not be exhausted by one or more exercises thereof or by any imperfect exercise thereof and shall not be extinguished by any judgment entered pursuant thereto. Such authority may be exercised on one or more occasions or from time to time in the same or different jurisdictions as often as Lender shall deem necessary or desirable, for all of which this Guaranty shall be a sufficient warrant.

Miscellaneous Provisions. The following miscellaneous provisions are a part of this Guaranty:

Amendments. This Guaranty, together with any Related Documents, constitutes the entire understanding and agreement of the parties as to the matters set forth in this Guaranty. No alteration of or amendment to this Guaranty shall be effective unless given in writing and signed by the party or parties sought to be charged or bound by the alteration or amendment.

Attorneys’ Fees; Expenses. Guarantor agrees that if Lender hires an attorney to help enforce this Guaranty, Guarantor will pay, subject to any limits under applicable law, Lender’s attorneys’ fees and all of Lender’s other collection expenses, whether or not there is a lawsuit and including without limitation additional legal expenses for bankruptcy proceedings.

Caption Headings. Caption headings in this Guaranty are for convenience purposes only and are not to be used to interpret or define the provisions of this Guaranty.

Governing Law. This Guaranty will be governed by, construed and enforced in accordance with federal law and the laws of the State of Maryland. This Guaranty has been accepted by Lender in the State of Maryland.

Integration. Guarantor further agrees that Guarantor has read and fully understands the terms of this Guaranty; Guarantor has had the opportunity to be advised by Guarantor’s attorney with respect to this Guaranty; the Guaranty fully reflects Guarantor’s intentions and parol evidence is not required to interpret the terms of this Guaranty. Guarantor hereby indemnifies and holds Lender harmless from all losses, claims, damages, and costs (including Lender’s attorneys’ fees) suffered or incurred by Lender as a result of any breach by Guarantor of the warranties, representations and agreements of this paragraph.

Interpretation. In all cases where there is more than one Borrower or Guarantor, then all words used in this Guaranty in the singular shall be deemed to have been used in the plural where the context and construction so require; and where there is more than one Borrower named in this Guaranty or when this Guaranty is executed by more than one Guarantor, the words “Borrower” and “Guarantor” respectively shall mean all and any one or more of them. If a court finds that any provision of this Guaranty is not valid or should not be enforced, that fact by itself will not mean that the rest of this Guaranty will not be valid or enforced. Therefore, a court will enforce the rest of the provisions of this Guaranty even if a provision of this Guaranty may be found to be invalid or unenforceable. If any one or more of Borrower or Guarantor are corporations, partnerships, limited liability companies, or similar entities, it is not necessary for Lender to inquire into the powers of Borrower or Guarantor or of the officers, directors, partners, managers, or other agents acting or purporting to act on their behalf, and any indebtedness made or created in reliance upon the professed exercise of such powers shall be guaranteed under this Guaranty.

JURY WAIVER. LENDER AND BORROWER AND GUARANTOR EACH HEREBY WAIVE TRIAL BY JURY IN ANY ACTION OR PROCEEDING TO WHICH LENDER OR BORROWER OR GUARANTOR MAY BE PARTIES, ARISING OUT OF, OR IN ANY WAY PERTAINING TO, THIS GUARANTY. IT IS AGREED THAT THIS WAIVER CONSTITUTES A WAIVER OF TRIAL BY JURY OF ALL CLAIMS AGAINST ALL PARTIES TO SUCH ACTIONS OR PROCEEDINGS. THIS WAIVER IS KNOWINGLY, WILLINGLY AND VOLUNTARILY MADE BY LENDER AND BORROWER AND GUARANTOR, AND LENDER AND BORROWER AND GUARANTOR EACH HEREBY REPRESENT THAT NO REPRESENTATIONS OF FACT OR OPINION HAVE BEEN MADE BY ANY INDIVIDUAL TO INDUCE THIS WAIVER OF TRIAL BY JURY OR TO IN ANY WAY MODIFY OR NULLIFY ITS EFFECT. BORROWER AND GUARANTOR EACH FURTHER REPRESENT THAT EACH HAS BEEN REPRESENTED IN THE SIGNING OF THIS GUARANTY AND IN THE MAKING OF THIS WAIVER BY INDEPENDENT LEGAL COUNSEL, SELECTED OF EACH’S OWN FREE WILL, AND THAT EACH HAS HAD THE OPPORTUNITY TO DISCUSS THIS WAIVER WITH COUNSEL.

Notices. Any notice required to be given under this Guaranty shall be given in writing, and shall be effective when actually delivered, if hand delivered, when actually received by telefacsimile (unless otherwise required by law), when deposited with a nationally recognized overnight courier, or, if mailed, when deposited in the United States mail, as first class, certified or registered mail postage prepaid, directed to the addresses shown near the beginning of this Guaranty. Any party may change its address for notices under this Guaranty by giving formal written notice to the other parties, specifying that the purpose of the notice is to change the party’s address. For notice purposes, Guarantor agrees to keep Lender informed at all times of Guarantor’s current address. Unless otherwise provided or required by law, if there is more than one Guarantor, any notice given by Lender to any Guarantor is deemed to be notice given to all Guarantors.

No Waiver by Lender. Lender shall not be deemed to have waived any rights under this Guaranty unless such waiver is given in writing and signed by Lender. No delay or omission on the part of Lender in exercising any right shall operate as a waiver of such right or any other right. A waiver by Lender of a provision of this Guaranty shall not prejudice or constitute a waiver of Lender’s right otherwise to demand strict compliance with that provision or any other provision of this Guaranty. No prior waiver by Lender, nor any course of dealing between Lender and Guarantor, shall constitute a waiver of any of Lender’s rights or of any of Guarantor’s obligations as to any future transactions. Whenever the consent of Lender is required under this Guaranty, the granting of such consent by Lender in any instance shall not constitute continuing consent to subsequent instances where such consent is required and in all cases such consent may be granted or withheld in the sole discretion of Lender.

COMMERCIAL GUARANTY

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Successors and Assigns. Subject to any limitations stated in this Guaranty on transfer of Guarantor’s interest, this Guaranty shall be binding upon and inure to the benefit of the parties, their heirs, personal representatives, successors and assigns.

Definitions. The following capitalized words and terms shall have the following meanings when used in this Guaranty. Unless specifically stated to the contrary, all references to dollar amounts shall mean amounts in lawful money of the United States of America. Words and terms used in the singular shall include the plural, and the plural shall include the singular, as the context may require. Words and terms not otherwise defined in this Guaranty shall have the meanings attributed to such terms in the Uniform Commercial Code:

Borrower. The word “Borrower” means Avatech Solutions Subsidiary, Inc. and includes all co-signers and co-makers signing the Note.

GAAP. The word “GAAP” means generally accepted accounting principles.

Guarantor. The word “Guarantor” means each and every person or entity signing this Guaranty, including without limitation William James Hindman.

Guaranty. The word “Guaranty” means the guaranty from Guarantor to Lender, including without limitation a guaranty of all or part of the Note.

Indebtedness. The word “Indebtedness” means Borrower’s indebtedness to Lender as more particularly described in this Guaranty.

Lender. The word “Lender” means K Bank, its successors and assigns.

Note. The word “Note” means the promissory note dated October 28, 2004, in the original principal amount of $700,000.00 from Borrower to Lender, together with all modifications of and renewals, replacements, and substitutions for the promissory note or agreement.

Related Documents. The words “Related Documents” mean all promissory notes, credit agreements, loan agreements, environmental agreements, guaranties, security agreements, mortgages, deeds of trust, security deeds, collateral mortgages, and all other instruments, agreements and documents, whether now or hereafter existing, executed in connection with the indebtedness.

EACH UNDERSIGNED GUARANTOR ACKNOWLEDGES HAVING READ ALL THE PROVISIONS OF THIS GUARANTY AND AGREES TO ITS TERMS. IN ADDITION, EACH GUARANTOR UNDERSTANDS THAT THIS GUARANTY IS EFFECTIVE UPON GUARANTOR’S EXECUTION AND DELIVERY OF THIS GUARANTY TO LENDER AND THAT THE GUARANTY WILL CONTINUE UNTIL TERMINATED IN THE MANNER SET FORTH IN THE SECTION TITLED “DURATION OF GUARANTY”. NO FORMAL ACCEPTANCE BY LENDER IS NECESSARY TO MAKE THIS GUARANTY EFFECTIVE. THIS GUARANTY IS DATED OCTOBER 28, 2004.

THIS GUARANTY IS GIVEN UNDER SEAL AND IT IS INTENDED THAT THIS GUARANTY IS AND SHALL CONSTITUTE AND HAVE THE EFFECT OF A SEALED INSTRUMENT ACCORDING TO LAW.

GUARANTOR:

William James Hindman

LASER PRO Lending, Ver. 5.24.00.003 Copr. Harland Financial Solutions, Inc. 1997, 2004. All Rights Reserved. - MD L:\CFI\LPL\E20.FC TR-701 PR-LOC