Exhibit
      10.4

    


    


    THIRD
      AMENDMENT TO PURCHASE AGREEMENT

    


    


    THIRD
      AMENDMENT TO PURCHASE AGREEMENT dated as of the 13th day of July, 2007 (the
      “Amendment”), by and between MOBILEPRO
      CORP.,
      a
      Delaware corporation having a place of business and mailing address of 6701
      Democracy Boulevard, Suite 202, Bethesda, Maryland 20817 (the “Seller”) and
UNITED
      SYSTEMS ACCESS, INC.,
      a
      Delaware corporation d/b/a U.S.A. Telephone having a place of business and
      mailing address of 5 Bragdon Lane, Kennebunk, Maine 04043 (the
“Buyer”).

     

    
      	1.	
              Reference
                to Purchase Agreement; Background.

            


    

     

    Reference
      is made to the Purchase Agreement dated as of June 29, 2007, by and between
      Seller and Buyer, as amended to date (as so amended, the “Purchase Agreement”).
      Capitalized terms used herein without definitions shall have the meanings
      assigned to them in the Purchase Agreement, as those meanings may be amended
      hereby.

     

    Seller
      and Buyer desire to amend the Purchase Agreement to, among other matters, (i)
      amend the indemnification obligations of Seller to specifically include certain
      claims as indemnifiable claims and (ii) provide that all Adverse Consequences
      sustained or incurred by Buyer arising from certain liens and claims shall
      be
      indemnifiable by Seller from dollar one with no time limit
      whatsoever.

    


    
      	2.	
              Amendments
                to Purchase Agreement.

            


    

     

    (a) Section
      10.1(a) of the Purchase Agreement is hereby amended by adding the following
      as
      subsection (vii) thereto:

    


    “(vii)
      Any and all claims, actions, suits, proceedings, and demands brought against
      Buyer and/or the Target Corporations by Thomas E. Mazerski and Deborah Mazerski
      (collectively, the “Mazerski Claims”).”

     

    (b) Section
      10.3 of the Purchase Agreement is hereby amended by adding the following as
      subsection (d) thereto:

    


    “(d)
      Notwithstanding Section 10.3(a) to the contrary, the Seller shall assume the
      defense of all Mazerski Claims and shall bear and be solely responsible for
      all
      costs and expenses in connection therewith, and
      shall
      have the right to assert any claims, including counterclaims, against Thomas
      E.
      Mazerski and/or Deborah Mazerski in connection with the employment of Thomas
      E.
      Mazerski and/or Deborah Mazerski at CloseCall during the period of time that
      CloseCall was a subsidiary of the Seller, and shall bear and be solely
      responsible for all costs and expenses in connection therewith. In the event
      that the Seller recovers for itself, the
      Buyer
      or any applicable Target Corporation
      on
any
      claims or counterclaims
      against Thomas E. Mazerski and/or Deborah Mazerski, the
      Seller
      shall keep the proceeds of such recovery and from such amounts shall
      reimburse the Buyer
      out of
      the proceeds of such recovery, from dollar one, for Buyer’s
      reasonable
      legal and
      other
expenses
      and court costs
      associated with participating
      in the litigation of
      the
      Mazerski Claims or claims brought by the Seller against Thomas E. Mazerski
      and/or Deborah Mazerski.

    


    
      
         

      

      
         

        
          

        

      

      
         

      

    

    (c) Section
      10.6 of the Purchase Agreement is hereby amended by deleting the same in its
      entirety and substituting therefore the following:

    


    “10.6.Limits
      On Indemnification.
      

     

    (a) Subject
      to Section 10.6(b) hereof, no amount shall be payable by any Indemnifying Party
      pursuant to this Agreement, unless the aggregate amount of Adverse Consequences
      subject to indemnification under Section 10.1 or 10.2 above, as the case may
      be,
      exceeds One Hundred Thousand and 00/100 Dollars ($100,000), at which point
      the
      Indemnified Party shall be entitled to all indemnification amounts accrued
      up to
      such threshold. Notwithstanding anything to the contrary in this Agreement,
      the
      maximum amount of indemnifiable Adverse Consequences which may be recovered
      by
      Buyer from Seller under this Article 10 shall be an amount equal to Eight
      Million One Hundred Thousand and 00/100 Dollars ($8,100,000). 

     

    (b) Notwithstanding
      the first part of this Section 10.6 above or any other provision of this
      Agreement to the contrary, the Seller shall indemnify and hold the Buyer and
      each of the Target Corporations, their officers, directors, employees, agents,
      affiliates, successors and assigns harmless from and with respect to any and
      all
      Adverse Consequences any Target Corporation or Buyer, or their respective
      successors and assigns, may sustain or incur, from
      dollar one,
      without
      any time limit whatsoever, related to or arising directly or indirectly out
      of
      (i) two Federal tax liens filed with the State of Texas Secretary of State
      against Inter Net Express Inc. on June 26, 1995 and September 8, 1995 as
      Instrument Nos. 9500126607 and 9500176387, respectively; and (ii) the Mazerski
      Claims.

     

    
      
        	3.	
                Miscellaneous.

              


      

    

     

    (a) This
      Amendment may be executed in any number of counterparts, each of which, when
      executed and delivered, shall be an original, but all counterparts shall
      together constitute one instrument. The terms and provisions of the Purchase
      Agreement and all other documents arising therefrom, related thereto, and
      executed in connection therewith, including, without limitation, the Related
      Agreements, as modified hereby, are hereby ratified and affirmed in all
      respects, continue in full force and effect and are made applicable to this
      Amendment. The Purchase Agreement and this Amendment shall be read and construed
      as a single agreement. All references to the Purchase Agreement in any documents
      arising therefrom, related thereto, and executed in connection therewith,
      including, without limitation, the Related Agreements, shall hereafter mean
      and
      refer to the Purchase Agreement, as amended hereby.

     

    
      
         

      

      
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    (c) This
      Amendment shall be governed by and construed in accordance with the laws of
      the
      State of Maine and shall be binding upon and inure to the benefit of the parties
      hereto and their respective successors and assigns.

     

    (d) Each
      party hereto hereby represents and warrants that this Amendment has been
      executed and delivered by duly authorized officers of each party and
      acknowledges and agrees that it will execute and deliver such additional
      amendments, agreements and documents as the other party may reasonably require
      to confirm the foregoing.

     

     

     

     

     

    


    [The
      balance of this page is intentionally left blank. The signature page
      follows.]

     

     

    
      
         

      

      
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    IN
      WITNESS WHEREOF, the parties hereto have duly caused this Amendment to be
      executed as of the day and year first above written.

     

     

    
      
        	 	 	 
	WITNESS:	BUYER
	 	 
	 	UNITED SYSTEMS ACCESS,
                INC.
	 
 	 
 	 
 
	 	By:  	/s/
                L. William Fogg 
	
                
 	
                
L.
                William Fogg, Chief Executive Officer
	 	 


      

       

      
        
          	 	 	 
	 	SELLER
	 	 
	 	MOBILEPRO CORP.
	 
 	 
 	 
 
	 	By:  	/s/
                  Jay O. Wright 
	
                  
 	
                  
Jay
                  O. Wright, Chairman and CEO
	 	 


        

      

       



    
      
        
        

      

      
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