Redirector errors

I have a laptop running Windows 2000 Service Pack 4 and when the user is
connected through ADSL and the Cisco VPN client they have problems saving
files to certain shares on the corp network. They also cannot reply to or
forward emails in Outlook, without getting a "Network problems are
preventing...". Yet when the laptop is connected to the trusted LAN in the
office all works fine. The Event Viewer reports Event ID 50 "The system was
attempting to transfer file data from buffers to \Device\LanmanRedirector..."
with source MrxSmb. Any ideas on what might be causing this? Thanks.

Regards,

Randy
.