Mapped Network drive freezes for few sec when any folder is accessed.

I am having the following issue:
I mapped a network drive to a Win Server 2003. However when I access it it takes ~20 sec before any new folder opens up. Any software initiallized on the remote drive also initializes for very long time to a point it is useless.

I believe it is related to credentials...

I use Workgroup and boths W2K3 Server and W7 Prof have accounts with the same name and password.

When I disconnect and restart then map - it works fine but after a restart (with mapp on initialization checked) it is very slow again.

No it isn't hybernating. There are 4 other workstations and they are all OK. Its the new one that does it. Indexing is enabled.
I have been searching other threads and forums but nothing so far.

What do you mean by scans network drive?

This is just a thought...

I have external hard drives that if they are not used, they go into sleep.

If my network access them, the network has to wait till the drives come out of sleep becuase they can be access; there for, the wait time.