"Port already active" when connecting to internet...

[Roguetech]

Using Win2K, I often get a message saying "Port is already active" message, and generally I have to reboot. I think it happens when two programs try to dial at the same time...? To rub salt in the wound, when it's shutting down and terminates the network connections, the modem begins dialing! Is there any way to make Win2K realize the modem isn't being used?