windows explorer slow

[mike]

If I right-click on a file (not an executable) when the
computer is connected to the network, it can take up to 1
minute for the drop-down box to appear.

As soon as I disconnect, WinXp file explorer works fine.

I have removed all shared drives, checked all users and
groups. I am convinced that this is a network
user 'rights' / and or security issue, but I have no idea
how to fix it.

Any help would be appreciated.

Thanks