On a 7 machine network running Norton Internet Security, we haven't had any problems with Messenger Service popups until recently.

I can't understand it. I can't do a "net-send" to any other machine because of the firewall. The "ShieldsUp" site shows all the machines as completely stealth. But the popups are still getting through.

I finally decided to just shut the messenger service down on all the machines, but with our setup it really shouldn't be necessary.

So my question is, HOW are these popups getting though when the firewall should be stopping them?