VPN problems with XP Pro

Hi, I have a problem with two laptops that use a dial up connection to access our host systems through a VPN.

The dial up works fine and they can connect to our server. The only problem is that they cannot access their emails through Outlook 2000. The most common error message is that there is a problem accessing the server. I know that each laptop is definately into our system as I can use Tiny Term to access our UNIX system.

I have checked the settings with other pc’s that link into the VPN and they are identical.

Any assistance would be appreciated, Regards Colin McKellar