My transition from a Windows to a Linux desktop has raised a few teething problems, almost the most annoying was the fact that I for some reason I could only VPN into certain MS PPTP VPN servers.
In the end I figured out that that the difference was I could VPN into Windows 2000 servers but not Windows 2003.
In the logs I was getting:
LCP terminated by peer (random load of symbols)
I tracked it down in the end to one setting under the PPTP config.
Under KNetworkManager this appears under ‘Compression & Encryption’, ‘Encryption’, ‘Require 128 bit MPPE encryption’. Check this and it all works.