Problem with tcp traffic on VPN connection router and Cisco VPN client 1.1

[admin_2]

I have a VPN connection between a Cisco VPN client 1.1 and a router 827. The VPN tunnel is OK, I can ping some machine on the local network but when I want to access to Exchange Server via Outlook, I can't. Or I try to access to network shared drive on a server from my client or a TSE client, I can't. It may be a problem on the TCP layer or a NAT/PAT problem however I don't NAT traffic between the local network and the client, only the traffic to Internet.

[#2]

a lot of times, outlook accesses the exchange server using the NetBIOS name. Do you have an ip address defined for your exchange server on the oulook client?

if you do, can you telnet to the exchange server on port 25.e.g,

telnet x.x.x.x 25

if that works, that means you have tcp connectivity and you are running into some MTU/fragmentation issues