Re: Norton Firewall blocking port 81

From: T. Sean Weintz (strap_at_hanh-ct.org)
Date: 07/08/05


Date: Fri, 08 Jul 2005 12:21:27 -0400

Mehdi wrote:
> 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

Sounds as if this is the one single security concious client you have.
It would seem all the others allow outgoing connections to any port,
which is BAD.

The client you are having problems with probably has all outgoing ports
blocked expecpt for the ones that are most commonly used (ie: 80, 8080,
20, 21, maybe 23, 119, etc) - which is how ANY internet connection to a
windoze box should be, IMO.

Norton Firewall should be configurable to specifically allow port 81
outgoing. However I am afraid I don't know the details on how, since I
do not use that product.



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