GUARANTEE     THIS GUARANTEE (“Guarantee”), dated October 25, 2005, is by each of the undersigned (eachindividually, a “Guarantor” and collectively, “Guarantors”) in favor of Wachovia Bank, NationalAssociation, a National Banking Association (“Lender”), having an office at 301 South CollegeStreet, Charlotte, NC 28288-0479.WITNESSETH:     WHEREAS, Lender has entered into financing arrangements pursuant to which Lender may makeloans and advances and provide other financial accommodations to US LEC Corp. (“Borrower”) as setforth in the Loan and Security Agreement, dated of even date herewith, by and among Borrower,certain affiliates of Borrower, and Lender (as the same now exists or may hereafter be amended,modified, supplemented, extended, renewed, restated or replaced, the “Loan Agreement”), and theother agreements, documents and instruments referred to therein or at any time executed and/ordelivered in connection therewith or related thereto, including, but not limited to, this Guarantee(all of the foregoing, together with the Loan Agreement, as the same now exist or may hereafter beamended, modified, supplemented, extended, renewed, restated or replaced, being collectivelyreferred to herein as the “Financing Agreements”); and     WHEREAS, due to the close business and financial relationships between Borrower and eachGuarantor, in consideration of the benefits which will accrue to Guarantors and as an inducementfor and in consideration of Lender making loans and advances and providing other financialaccommodations to Borrower pursuant to the Loan Agreement and the other Financing Agreements;     NOW, THEREFORE, in consideration of the premises and for other good and valuableconsideration, the receipt and sufficiency of which are hereby acknowledged, each Guarantor herebyjointly and severally agrees in favor of Lender as follows:     1. Guarantee.     (a) Each Guarantor absolutely and unconditionally, jointly and severally, guarantees andagrees to be liable for the full and indefeasible payment and performance when due of all of theObligations, as defined in the Loan Agreement (all of which are collectively referred to herein asthe “Guaranteed Obligations”)     (b) This Guarantee is a guaranty of payment and not of collection. Each Guarantor agrees thatLender need not attempt to collect any Guaranteed Obligations from Borrower, any one of Guarantorsor any other Obligor or to realize upon any Collateral, but may require any one of Guarantors tomake immediate payment of all of the Guaranteed Obligations when due, whether by maturity,acceleration or otherwise, or at any time thereafter. Lender shall apply any amounts received inrespect of the Guaranteed Obligations to any of the Guaranteed Obligations, in whole or in part(including attorneys’ fees and legal expenses incurred by

 
Lender with respect thereto or otherwise chargeable to Borrower or Guarantors) and in suchorder as Lender may elect.     (c) Payment by Guarantors shall be made to Lender at the office of Lender from time to time ondemand as Guaranteed Obligations become due. Guarantors shall make all payments to Lender on theGuaranteed Obligations free and clear of, and without deduction or withholding for or on accountof, any setoff, counterclaim, defense, duties, taxes, levies, imposts, fees, deductions,withholding, restrictions or conditions of any kind. One or more successive or concurrent actionsmay be brought hereon against any Guarantor either in the same action in which Borrower or any ofthe other Guarantors or any other Obligor is sued or in separate actions.     2. Waivers and Consents.     (a) Notice of acceptance of this Guarantee, the making of loans and advances and providingother financial accommodations to Borrower and presentment, demand, protest, notice of protest,notice of nonpayment or default and all other notices to which Borrower or any of Guarantors areentitled are hereby waived by each Guarantor. Each Guarantor also waives notice of and herebyconsents to, (i) any amendment, modification, supplement, extension, renewal, or restatement of theLoan Agreement and any of the other Financing Agreements that is signed by an authorized officer ofBorrower, including, without limitation, extensions of time of payment of or increase or decreasein the amount of any of the Guaranteed Obligations, the interest rate, fees, other charges, or anyCollateral, and the guarantee made herein shall apply to the Loan Agreement and the other FinancingAgreements and the Guaranteed Obligations as so amended, modified, supplemented, renewed, restatedor extended, increased or decreased, (ii) the taking, exchange, surrender and releasing ofCollateral or guarantees now or at any time held by or available to Lender for the obligations ofBorrower or any other party at any time liable on or in respect of the Guaranteed Obligations orwho is the owner of any property which is security for the Guaranteed Obligations (individually, an“Obligor” and collectively, the “Obligors”), including, without limitation, the surrender orrelease by Lender of any one of Guarantors hereunder, (iii) the exercise of, or refraining from theexercise of any rights against Borrower, any Guarantor or any other Obligor or any Collateral, (iv)the settlement, compromise or release of, or the waiver of any default with respect to, any of theGuaranteed Obligations and (v) any financing by Lender of Borrower under Section 364 of the UnitedStates Bankruptcy Code or consent to the use of cash Collateral by Lender under Section 363 of theUnited States Bankruptcy Code. Each Guarantor agrees that the liability of Guarantors hereundershall not be otherwise impaired or affected by any of the foregoing.     (b) No invalidity, irregularity or unenforceability of all or any part of the GuaranteedObligations shall affect, impair or be a defense to this Guarantee, nor shall any othercircumstance which might otherwise constitute a defense available to or legal or equitabledischarge of Borrower in respect of any of the Guaranteed Obligations, or any one of Guarantors inrespect of this Guarantee, affect, impair or be a defense to this Guarantee. Without limitation ofthe foregoing, the liability of Guarantors hereunder shall not be discharged or impaired in anyrespect by reason of any failure by Lender to perfect or continue perfection of any lien orsecurity interest in any Collateral or any delay by Lender in perfecting any such lien or securityinterest. As to interest, fees and expenses, whether arising before or after the commencement ofany case with respect to Borrower under the United States
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Bankruptcy Code or any similar statute, Guarantors shall be liable therefor, even ifBorrower’s liability for such amounts does not, or ceases to, exist by operation of law. EachGuarantor acknowledges that Lender has not made any representations to any Guarantor with respectto Borrower, any other Obligor or otherwise in connection with the execution and delivery byGuarantors of this Guarantee and Guarantors are not in any respect relying upon Lender or anystatements by Lender in connection with this Guarantee.     (c) Until the Guaranteed Obligations are paid in full, each Guarantor hereby irrevocably andunconditionally waives and relinquishes all statutory, contractual, common law, equitable and allother claims against Borrower, any Collateral for the Guaranteed Obligations or other assets ofBorrower or any other Obligor, for subrogation, reimbursement, exoneration, contribution,indemnification, setoff or other recourse in respect to sums paid or payable to Lender by eachGuarantor hereunder and each Guarantor hereby further irrevocably and unconditionally waives andrelinquishes any and all other benefits which Guarantors might otherwise directly or indirectlyreceive or be entitled to receive by reason of any amounts paid by or collected or due fromGuarantors, Borrower or any other Obligor upon the Guaranteed Obligations or realized from theirproperty.     3. Subordination. All amounts now or hereafter owed to any or all of Guarantors byany Borrower or any other Obligor under this Guarantee is hereby subordinated in right of paymentto the indefeasible payment in full to Lender of the Guaranteed Obligations and all such amountsand any security and guarantees therefor are hereby assigned to Lender as security for theGuaranteed Obligations.     4. Acceleration. Upon the receipt of notice by Borrower from Lender in accordance withSection 10.2(b) of the Loan Agreement of the acceleration of the Obligations and demand forimmediate payment thereof, the liability of Guarantors for the entire Guaranteed Obligations shallmature and become immediately due and payable, even if the liability of any or all of Borrower orany other Obligor therefor does not, upon the occurrence of any act, condition or event whichconstitutes an Event of Default as such term is defined in the Loan Agreement.     5. Account Stated. The books and records of Lender showing the account between Lenderand Borrower shall be admissible in evidence in any action or proceeding against or involvingGuarantors as presumptive evidence of the items therein set forth, and the monthly statements ofLender rendered to Borrower, to the extent to which no written objection is made within thirty (30)days from the date such statement has been received by Borrower, shall be deemed conclusivelycorrect and constitute an account stated among Lender and Borrower and be binding on Guarantors.     6. Termination. This Guarantee is continuing, unlimited, absolute and unconditional.All Guaranteed Obligations shall be conclusively presumed to have been created in reliance on thisGuarantee. Each Guarantor shall continue to be liable hereunder until one of Lender’s officersactually receives a written termination notice from a Guarantor sent to Lender at its address setforth above by certified mail, return receipt requested and thereafter as set forth below. Suchnotice received by Lender from any Guarantor shall not constitute a revocation or termination ofthis Guarantee as to any of the other Guarantors. Revocation or termination hereof by anyGuarantor shall not affect, in any manner, the rights of Lender or any obligations or duties of anyGuarantor (including the Guarantor which may have sent such notice) under
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this Guarantee with respect to (a) Guaranteed Obligations which have been created, contracted,assumed or incurred prior to the receipt by Lender of such written notice of revocation ortermination as provided herein, including, without limitation, (i) all amendments, extensions,renewals and modifications of such Guaranteed Obligations (whether or not evidenced by new oradditional agreements, documents or instruments executed on or after such notice of revocation ortermination), (ii) all interest, fees and similar charges accruing or due on and after revocationor termination, and (iii) all attorneys’ fees and legal expenses, costs and other expenses paid orincurred on or after such notice of revocation or termination in attempting to collect or enforceany of the Guaranteed Obligations against Borrower, Guarantors or any other Obligor (whether or notsuit be brought), or (b) Guaranteed Obligations which have been created, contracted, assumed orincurred after the receipt by Lender of such written notice of revocation or termination asprovided herein pursuant to any contract entered into by Lender prior to receipt of such notice.The sole effect of such revocation or termination by any Guarantor shall be to exclude from thisGuarantee the liability of such Guarantor for those Guaranteed Obligations arising after the dateof receipt by Lender of such written notice which are unrelated to Guaranteed Obligations arisingor transactions entered into prior to such date. Without limiting the foregoing, this Guaranteemay not be terminated and shall continue so long as the Loan Agreement shall be in effect (whetherduring its original term or any renewal, substitution or extension thereof); provided, that, aGuarantor’s obligation hereunder shall be released and terminated upon the disposition of all ofthe outstanding equity of such Guarantor so long as such disposition complies with the terms asconditions of Section 9.7 of the Loan Agreement.     7. Reinstatement. If after receipt of any payment of, or proceeds of Collateralapplied to the payment of, any of the Guaranteed Obligations, Lender is required to surrender orreturn such payment or proceeds to any Person for any reason, then the Guaranteed Obligationsintended to be satisfied by such payment or proceeds shall be reinstated and continue and thisGuarantee shall continue in full force and effect as if such payment or proceeds had not beenreceived by Lender. Each Guarantor shall be liable to pay to Lender, and does indemnify and holdLender harmless for the amount of any payments or proceeds surrendered or returned. This Section 7shall remain effective notwithstanding any contrary action which may be taken by Lender in relianceupon such payment or proceeds. Except as set forth in the last sentence of Section 6 above withrespect to any Guarantor, this Section 7 shall survive the termination or revocation of thisGuarantee.     8. Amendments and Waivers. Neither this Guarantee nor any provision hereof shall beamended, modified, waived or discharged orally or by course of conduct, but only by a writtenagreement signed by an authorized officer of Lender and Borrower or Guarantor. Lender shall not byany act, delay, omission or otherwise be deemed to have expressly or impliedly waived any of itsrights, powers and/or remedies unless such waiver shall be in writing and signed by an authorizedofficer of Lender. Any such waiver shall be enforceable only to the extent specifically set forththerein. A waiver by Lender of any right, power and/or remedy on any one occasion shall not beconstrued as a bar to or waiver of any such right, power and/or remedy which Lender would otherwisehave on any future occasion, whether similar in kind or otherwise.     9. Corporate Existence, Power and Authority. Each Guarantor is a corporation orlimited liability company, as the case may be, duly organized and in good standing under the
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laws of its state of incorporation or formation, as the case may be, and is duly qualified asa foreign corporation or limited liability company, as the case may be, and in good standing, ifapplicable, in all states where the nature and extent of the business transacted by it or theownership of assets makes such qualification necessary, except for those jurisdictions in which thefailure to so qualify would not have a material adverse effect on the financial condition, resultsof operation or businesses of any Guarantor or the rights of Lender hereunder or under any of theother Financing Agreements. The execution, delivery and performance of this Guarantee is withinthe corporate powers or limited liability company powers, as the case may be, of each Guarantor,have been duly authorized and are not in contravention of law or the terms of the certificates ofincorporation, articles of organization or certificate of formation, as the case may be, by-laws oroperating agreement, as the case may be, or other organizational documentation of any suchGuarantor, or any indenture, agreement or undertaking to which any such Guarantor is a party or bywhich any such Guarantor or its property are bound. This Guarantee constitutes the legal, validand binding obligation of each Guarantor enforceable in accordance with its terms. Any Guarantorsigning this Guarantee shall be bound hereby whether or not any of the other Guarantors or anyother person signs this Guarantee at any time.     10. Governing Law; Choice of Forum; Service of Process; Jury Trial Waiver.     (a) The validity, interpretation and enforcement of this Guarantee and any dispute arising outof the relationship between any Guarantor and Lender, whether in contract, tort, equity orotherwise, shall be governed by the internal laws of the State of North Carolina, but excluding anyprinciples of conflicts of law or other rule of law that would cause the application of the law ofany jurisdiction other that the laws of the State of North Carolina.     (b) Each Guarantor hereby irrevocably consents and submits to the non-exclusive jurisdictionof the Superior Court for North Carolina, Mecklenburg County and the United States District Courtfor the Western District of North Carolina and waives any objection based on venue or forumnonconveniens with respect to any action instituted therein arising under thisGuarantee or any of the other Financing Agreements or in any way connected with or related orincidental to the dealings of any Guarantor and Lender in respect of this Guarantee or any of theother Financing Agreements or the transactions related hereto or thereto, in each case whether nowexisting or hereafter arising and whether in contract, tort, equity or otherwise, and agrees thatany dispute arising out of the relationship between any Guarantor or Borrower and Lender or theconduct of any such persons in connection with this Guarantee, the other Financing Agreements orotherwise shall be heard only in the courts described above (except that Lender shall have theright to bring any action or proceeding against any Guarantor or its property in the courts of anyother jurisdiction which Lender deems necessary or appropriate in order to realize on anyCollateral at any time granted by Borrower or any Guarantor to Lender or to otherwise enforce itsrights against any Guarantor or its property).     (c) Each Guarantor hereby waives personal service of any and all process upon it and consentsthat all such service of process may be made by certified mail (return receipt requested) directedto its address set forth on the signature pages hereof and service so made shall be deemed to becompleted five (5) days after the same shall have been so deposited in the U.S. mails, or, atLender’s option, by service upon any Guarantor in any other manner provided under the rules of anysuch courts. Within thirty (30) days after such service, any Guarantor so served shall appear inanswer to such process, failing which such Guarantor shall
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be deemed in default and judgment may be entered by Lender against such Guarantor for theamount of the claim and other relief requested.     (d) EACH GUARANTOR HEREBY WAIVES ANY RIGHT TO TRIAL BY JURY OF ANY CLAIM, DEMAND, ACTION ORCAUSE OF ACTION (i) ARISING UNDER THIS GUARANTEE OR ANY OF THE OTHER FINANCING AGREEMENTS OR (ii)IN ANY WAY CONNECTED WITH OR RELATED OR INCIDENTAL TO THE DEALINGS OF ANY OF GUARANTORS AND LENDERIN RESPECT OF THIS GUARANTEE OR ANY OF THE OTHER FINANCING AGREEMENTS OR THE TRANSACTIONS RELATEDHERETO OR THERETO IN EACH CASE WHETHER NOW EXISTING OR HEREAFTER ARISING, AND WHETHER IN CONTRACT,TORT, EQUITY OR OTHERWISE. EACH GUARANTOR HEREBY AGREES AND CONSENTS THAT ANY SUCH CLAIM, DEMAND,ACTION OR CAUSE OF ACTION SHALL BE DECIDED BY COURT TRIAL WITHOUT A JURY AND THAT ANY GUARANTOR ORLENDER MAY FILE AN ORIGINAL COUNTERPART OF A COPY OF THIS AGREEMENT WITH ANY COURT AS WRITTENEVIDENCE OF THE CONSENT OF GUARANTORS AND LENDER TO THE WAIVER OF THEIR RIGHT TO TRIAL BY JURY.     (e) Lender shall not have any liability to Guarantors (whether in tort, contract, equity orotherwise) for losses suffered by Guarantors in connection with, arising out of, or in any wayrelated to the transactions or relationships contemplated by this Guarantee, or any act, omissionor event occurring in connection herewith, unless it is determined by a final and non-appealablejudgment or court order binding on Lender that the losses were the result of acts or omissionsconstituting gross negligence or willful misconduct. In any such litigation, Lender shall beentitled to the benefit of the rebuttable presumption that it acted in good faith and with theexercise of ordinary care in the performance by it of the terms of the Loan Agreement and the otherFinancing Agreements.     11. Notices. All notices, requests and demands hereunder shall be in writing anddeemed to have been given or made: if delivered in person, immediately upon delivery; if by telex,telegram or facsimile transmission, immediately upon sending and upon confirmation of receipt; ifby nationally recognized overnight courier service with instructions to deliver the next businessday, one (1) business day after sending; and if by certified mail, return receipt requested, five(5) days after mailing. All notices, requests and demands upon the parties are to be given to thefollowing addresses (or to such other address as any party may designate by notice in accordancewith this Section):   If to any Guarantor: US LEC Corp.