Let's consider 2 sites:
A: client site (where I may change the config of the router if necessary)
B: server site (where I've NO authority on server nor router config)
I try to use the standard PPtP VPN of Windows 2003. TCP 1723 + GRE are correctly configured on the B site to enable NAT for the VPN.
My observation is : if A or B routers are not Cisco, the VPN works correctly.
If A and B routers are Cisco, then when connecting, the client hangs on "verifying username and password".
I reproduce this situation with several routers:
A = Cisco Soho96 and B = Cisco 878
A = Cisco 831 and B = Cisco 827
A = Cisco 878 and B = Cisco 827
What could be changed in the router of A to let this VPN work correctly in every situation?
Thanks in advance,