Norton Firewall blocking port 81

From: Mehdi (vioccc_at_REMOVEME.gmail.com)
Date: 07/08/05 

Date: Fri, 8 Jul 2005 13:59:46 +0100

Hi,

We have developped a client application that initiates TCP connections to
our server applications on several ports including port 81. One of our
client has had some problem using our client application on his machine.
The application was able connect to most of our server applications fine
but not to the one listening on port 81. It turned out that this client had
Norton Firewall (don't know which version yet) installed and that shutting
down his firewall allowed him to connect just fine.

We off course don't want to ask our clients to shut down their firewall
applications so i'd like to find out what was wrong with his setup. The
client application definitively doesn't listen for incoming connection so
this can't be the problem. I do not know how Norton Firewall can be
configured so before asking our client to mess around with his firewall
settings, i'd like to know if there are any known issues with Norton
Firewall and port 81 and what simply steps could be done to solve this
problem. I have not found anything particular about that on the Web but if
you have some advices, i'd be glad to hear them.

Thanks

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