At work we have a intranet and we have to wait 10-15 seconds even sometimes! Nothing really changed from before we had this "bug". Just your regular security updates from microsoft.
We use Windows XP on 2003 servers. We couldn't find much wrong, nor could our IT partners. We've sent the problem to Microsoft. This was 2 months ago. They have yet to come up with the CAUSE of this problem, let alone the solution!!
So this may be related, but this is unknown. As far as i know we have not yet double-checked with other companies to see if they are experiencing simular problems, but our IT partner has not indicated this is the case (which i trust they will if they find out). As for MicroSoft: if this is a more common problem, they'll probly try to keep it quiet as much as possible....
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In more detail:
There's a lag every first time we try to access a mapped drive (network path that is mapped into a single drive letter for easy access). Once IN this mapped drive, you can browse and work without a problem. But if you wait several minutes (maybe 5 or 10 mins), the first access (even if your explorer is still residing in that same drive) has this lag again.
Also when changing to another mapped drive. But when you go back to the other drive, you can still access it quite fast.
One odd thing we've discovered; when doing the folowwing steps, there's no problem whatsoever:
Log into your own computer local administrator. Then when you want to access a network drive, you will be prompted for login: now log in as you normally would with your network login/password and all is fine.
Same thing applies when you log into a Terminal Server and from there access the network, so in theory we could get it to work, but this is not what we want. Microsoft has a bug, and we don't want to use work-arounds coz THEY can't find the cause!
oh.. good luck ! (try my suggestions to see if this is a simualr problem - and contact microCRAP if it is - and you have a legal version of windows of course)