System slowdown & can't disconnect from Web folder

Hi,

In My Network Places, I have a connection set up to a folder on a SharePoint
Server site. After I boot up, I can click the folder in My Network Places
from within Windows Explorer. It asks for my credentials, and then I'm in
until the next reboot.

The problem is that once I've authenticated, my entire system is slowed
down. I'm not sure why that is so, but I thought that an easy fix would be to
disconnect (rather than having to reboot or just live with the slowness).
However, I can't find a way to disconnect.

Right-clicking the folder does not produce any Disconnect option (although
this option is there in Windows Vista). Disconnect
Network Drive doesn't work because I haven't mapped to any drives.

Any ideas?

Thanks!