Unable to connect with Listening VNC Viewer

[Geza Levai]

   Hello Mick,
   Thanks for your thorough response to my email.

     >    Is  there a way to change the default value of the target port
     of 5500
     >    on the server side?
     Yes, go to the VNC server Connections tab.  BTW, I thought that the
     default
     port is 5900, not 5500.

   We're not talking about the same port. The default port of 5900 is for
   accessing  your  PC on port 5900 from a client machine by doing it the
   "old fashioned" way.
   The  port  of 5500 is for the sole purpose of making the connection by
   using  Listening  VNC  viewer  on  the client TO the server machine by
   having  the  server  machine  initiate  the contact to the "listening"
   viewer client.
   (by  right  clicking  on the VNC icon in the system tray then entering
   the  IP address of the viewer machine while the viewer machine has the
   Listening VNC viewer running.)
   So,  this  is  the port that my question was about, whether there is a
   way to change it somehow, even if it's through the registry.

     >    How can I troubleshoot this problem?
     >From   his  home  machine  telnet  into  your  <client_IP_address>
     <port_number>.
     Repeat  from  his  work machine and compare responses.  However, if
     his work
     sysadmin  are worth their salt, they would have disabled the telnet
     executable
     on his work computer.  Bring it in using a floppy/USB stick, or use
     Knoppix.
     HTH.
     --
     Regards,
     Mick

   This sounds like a great idea, I will give this a try.
   Thanks!
   Geza