I frequently have to connect to different VPN servers. Those servers have different VPN protocols implemented. Therefore I have to use Cisco VPN client and Microsofts' built-in VPN client in Windows 7. After installing Cisco VPN client the other one does not work any more. The Microsoft client hangs on "Verifying user name and password" if I try to connect to a PPTP server. After a couple of seconds it drops the connection with error number 619.
I can connect to that PPTP server from another Windows 7 without Cisco VPN client installed. It seems that if the Cisco sw installed, the PPTP client does not get any GRE pockets from the PPTP server.
Is it possible that the Cisco VPN client blocks incoming GRE pockets if they are targeted to an interface different from the one used by the Cisco client?
Thanks in advance for advices!