Hi Erik:

Yeah, I was using the internet to map drives on my company LAN.

I also hear it is becoming increasingly more common for ISPs to disable UDP ports 137 and 138 and TCP port 139 on their routers to reduce network traffic and tighten security. MS networking components rely on these ports, especially port 139 for NetBIOS communication.

Someone forwarded me an article (Q170998) from www.technet.com that explains the whole situation. Check it out.

Charlie