So, it appears as if the PHD - VRX does not like it when my PC is on line.
1. Do you have another PC, or a 2nd bootable drive with XP?
2. How about trying another server program?
3. How about a different based program: UPnP vs DLNA?
4 How about using XP instead of Seven?
5. Have you tried a direct connection w/o the router?
6. Do you have another router you could try?
7. If you disconnect your broadband feed, does that change anything?
8. Have you tried static IP addresses?
9. If you uncheck getting Internet time, does that change anything?
10. Do you have any additional firewalls, any other blocking provisions set on that router?
11. Can you boot into safe mode and still run that program?
12. Do you have a Virus program that scans your network? If so, disable it and see if that matters.
The idea with #11 is to stop everything that is not needed from running and see if another service or program is causing the conflict.