Remote Debugging?

Hello Folks:

 

   Developing in Win 7 Ultra, Visual Studio 2010 Pro, C++, Norton Security Suite from Comcast Version 5.1.0.29. 

 

   An app I'm developing runs on my Win 7 PC, but fails to run on my XP PC. 

 

   I'm attempting my first remote debugging session: 

 

      Start Visual Studio on the Win 7 PC.

 

      Start the remote debugger monitor on the XP PC.

 

      Attach to process on the Win 7 PC.

 

         Select

 

            Transport - Default

 

            Qualifier - <Name of XP PC>

 

               Error Message:

 

                   Unable to connect to the Microsoft Visual Studio Remote Debugging
                   Monitor named <Name of XP PC>.  Access is denied.

 

   I have no idea what the problem is, but I'd like to make sure the port the remote debugger needs is open.  This port is 135 TCP.  I'm not sure what my "Domain Policy" is, but I might also need 500, 4500 UDP open.  

 

   I've looked at Norton's firewall settings, and find no option to open a particular port. 

 

   How do I open a port by number?

 

      Thanks

      Larry