Just ran into a strange issue after upgrading my home network. I got a switch that all devices in my home network are connected to (dumb switch - it al hooks up to a Cisco E2000 for ips). Anyways... after switching everything over to this new setup, I ran into two issues.
First, my gigabit network was no longer gigabit, even though all lights on the switch indicated that it was gigabit. Network properties in connected computers also indicated gigabit speeds, but actual file transfers were at fast ethernet speeds.
Second, I could no longer connect to my WHS via windows explorer from my Win 7 Pro machine, when typing in the computer name (eg: \\server). It was like the computer didn't exist on the network. However, the server would respond to pings. I could do a nslookup, and everything worked correctly. Also, I could type in my server ip in windows explorer, and it worked (eg: \\192.168.1.100).
I then ran into this forum: http://www.geekzone.co.nz/forums.asp?forumid=74&topicid=38789
The suggestion is to run the following command in the command prompt: netsh int ip reset c:\resetlog.txt
Running the command on my Win 7 Pro box fixed the issue (after a restart). I could now transfer at gigabit speeds, and the name resolved properly in windows explorer.
I guess something was wrong with my TCP/IP stack, and this fixed the issue. I still have no clue how it got messed up in the first place, and exactly what was wrong.