Windows Explorer/Explorer bar hangs when connected to VPN

> Hi,
>
> running win xp w/sp2. The xp-client is behind an ISA-server, and I'm
> connecting to work through VPN using a smartcard. I can establish a VPN
> connection just fine, however my problem is local - after connecting to
> VPN. If I for example click on one of the icons in my quick launch bar, or
> switch to an explorer window I already have open, it can hang for 10-60
> seconds. If I try to switch to an explorer window which is open, and it
> hangs, it will stop hanging the second I disconnect my VPN connection. If
> I switch to for example a terminal service window which is already open I
> can work just fine there, without any hangs. It seems like everything is
> related to windows explorer, and it's not the entire computer
> hanging/freezing. I have a single mapping to my domain controller, which I
> also tried to disable without any results. The problems occurs randomly,
> and it can work fine for a few minutes before one of the explorer
> processes hangs again. Everything always resumes just fine (even explorer
> windows listed 'not responding') once I disconnect the vpn connection.
>
> Anyone have ideas on where to start troubleshooting? It's most likely not
> related to my smartcard reader or the smartcard reader drivers (tried
> switching out hardware).
>
> In advance, thank you.
> PaalB
>