10061 error

I have program that gets and uses an XML file from the internet. It works on most computers but on one particular computer it repeatedly generates an exception with message "No connection could be made because the target machine actively refused it 127.0.0.1:5555" and error code 10061.

On this computer I ran a registry repair software that fixed over 1,000 errors and left 13 it could not fix. The exception running my program on this computer still persists.

any ideas on how to proceed in resolving this problem?

I forgot to mention I put an exception for the program in the firewall and even tried running it with the firewall turned off. This had no effect on the problem