Vista explorer not responding when accessing network drive

Vista sucks! :-D
But i am stating the obvious. The particular problem i am having here is that explorer constantly hangs when accessing a network drive, sometimes for minutes on end, and it becomes slow to open any other explorer window (i.e. to try and do something else while i wait).

Most of the time i can access the network drive no problems, i just type \\server\blah and press enter. But occasionally (perhaps if the server is slow or there is some other problem with the network) it will hang and the title bar will say "(not responding)" and all that.
One time i couldn't even run a local program because the entire explorer was hung and for some reason it took a long time to start the program when i double-clicking on it.
I think it also happens if i map the network directory to a drive.

Today i though of a way to test whether it was the network or explorer. I started up PowerShell and cd'd to the directory. Went straigh to it. All the while explorer was still waiting.

Does anyone know why this might be happening (appart from "Vista sucks" )? Is it a known Vista/Windows problem?
I checked the event logs and although there are a number of events logged for this morning, none of them are around the time when the hang happened.
The anti-virus i am running is McAfee VirusScan & AntiSpyware Enterprise 8.7.0i if that helps. Perhaps it is thrashing the network trying to scan every single file that i browse to or something.

 

Anyone? I have googled it but none of the results are quite the same problem that i am having (most are actually due to a network problem or something else entirely). Also, i don't get this problem very often. I am constantly (read: every day) accessing network drives and this problem only happens on average once a week, but often enough to be annoying.