site to site VPN tunnel, WIN7 very slow to login

[1101]

Hi there. Ive setup a site to site VPN tunnel, via 2 hardware firewalls, with DHCP pass-through

on the remote site:
- Xp can login to the HEAD OFFICE domain server(2003) fairly quickly (login to the main sites domain)
- Win7 takes a very long time to login to windows (login to the main sites domain)
- The Win7 PC's didnt have this issue when they were physically at the head office

2 Win7 PC have this issue, XP (old dunga) logs into the remote domain reasonbly quickly
So obviously something strange with the Win7 login process. Is this just the way it is ??
Has anyone else come across the same issue ??
Any suggestions appreciated

Cheers

[tmrafi]

You will have to look at your Path MTU.
The moment you use a site to site VPN, your effective MTU goes down from 1500 to around 1436. If the firewalls are configured to pass the Path MTU then Windows will see it and will drop its MTU automatically. To troubleshoot you can set MTU manually to 1400 on your Win7 PC and check
The second issue is Kerberos. If you use Kerberos over TCP then you wont have issues, however if you use Kerberos over UDP (default in XP) you will have issues. It is strange that for you XP is working correctly and Win7 is misbehaving

[nmercer]

are cached creds not working?