SBS2003 server at main office
6 x WinXP remote clients using PPTP VPN to connect to RRAS on the server.
This morning I've had calls from all of the remote workers complaining they cannot connect to the VPN. Having checked their PCs I find that I can telnet to port 1723 on all their machines - but I cannot establish a connection using the Connection Manager profile.
The only way to resolve the issue was to delete the profile and reinstall.
All working ok now.
But what would have caused this in the first place? I checked all their PCs for recent updates - none of them have any that were installed within the last week. They've been using the same setup for around 2 years now without issue.