We run a MS 2003 Server running Routing and Remote Access server as our office default gateway. This server connects to the internet and creates VPN connections to remote sites. It also runs the DHCP service.
Since installing the Cisco VPN Client version 4.8.01.0300 the XP clients on the network are unable to view some websites (such as microsoft or experts-exchange) and commit some network functionality. To get the clients working we have to install and the uninstall the VPN Client software on each PC!
Uninstalling the VPN Client software from the routing and remote access server does not solve the problem - it has obviosuly made a change to the box that is not un-done by an uninstall.
This is causing us a real headache so if anyone has any ideas then they would be much appreciated.
A customer has issued this version of the VPN Client so I am unsure if we can simply upgrade. I also doubt upgrading will undo whatever has affected the routing and remote access server! I am hoping someone can tell me a nice registry key to delete or something similar!
This problem could be MTU issues. The problem occurs because many web servers block ICMP messages and the packets are dropped. As a result, the requested web site doesn't load. This problem is caused also by an incompatible MTU networking setting. You may try to install the latest SP. If you use MS ICS, you may want to configure all your Client computers to use the new, lower MTU as the default for all Internet communication. To modify the MTU size, locate the following registry key: HKEY_LOCAL_MACHINE\ SYSTEM\ CurrentControlSet\ Services\ Tcpip\ Parameters\ Interfaces. If you use a router like Cisco DSL Router, you may want to adjusting the PPPoE MTU Size. For example, to adjusting the PPPoE MTU Size on the Cisco DSL Router, do
ip adjust-mss 1452