Mydoom fix breaks internet connectivity.

[Ville Salo]

Symptom of this problem is that after a while of computer of use, all
new connections stop opening, even though old connections stay open.
Observing network traffic reveals that all connections made on local
ports 3127 or higher remain in syn_sent state. This port is used by
the mydoom virus and this makes me suspicious whether the patch
protecting from this virus has disabled local ports 3127 but not
binded them, so Windows still tries to use them.
It is also just as possible that this is an issue at the firewall box
upstream.

 

[Ville Salo]

It is also just as possible that this is an issue at the firewall box
upstream.

This is exactly what it proved out to be. They had blocked all traffic
in ports 3127-3198, it is now working. If anyone else is having
similar problems, ie. not being able to make a new connections after a
while of using windows, just try reloading different pages for a while
and you'll be able to connect again. Then contact your service
provider about this.