Nortel Contivity VPN Client V4_60.51 gets disconnected

[Synyc]

Windows 2000 pro.
T1 to the internet with Firebox II for firewall.

Client can connect to the VPN with no problems. After a few minutes he gets disconnected with the following error.

"The routing table cannot be altered after the Contivity VPN connection has been established. The contivity VPN Connection has been closed."

I can't figure out what may be trying to alter the routing table. We have one other client connecting to the vpn on our network and he has no problems.
Both clients are using dhcp. I found something on the net about disabling "DYNAMIC DNS REGISTRATION" in the registry. I attempted to do this but it didn't work. I wonder if I did it wrong.

Thanks

 

[CrapCram]

Guys,

We've experienced the same problem on our NT4's. We've solved this by lowering the MTU size on the IPSecShm7 adapter. Not sure if this adapter exists on all environments, but I'm sure there must be one alike.

You can change the MTU in the registry:
HKLM\System\CurrentControlSet\Services\IPSecShm7\Parameters\tcpip
Enter a DWORD called "MTU" and give it a value of 1200 (decimal).

If still not working, try to decrease some more.

This also should work on Win2000 although the MTU value could be located somewhere else. I'm sure you can easily find that on the Inet.

Hope it helps ...