VPN setup for PPTP

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Guest

I am having difficulty when trying to authenticate to the VPN server we have
configured.
I have configured the required Remote Access Policy in RRAS; I try to
connect each time and I get " Verifying username and password", but I am
never authenticated and the VPN connection never establishes.
The Server Status in RRAS is UP. The PPTP and L2TP ports all show Inactive.
I have "Grant Access" selected in the Remote Access Policy.
Any suggestions would be welcome.
Thank You.
 
Assuming you receive the error 800, you may want to check the status of IP port 47 (GRE).

Bob Lin, MS-MVP, MCSE & CNE
Networking, Internet, Routing, VPN Troubleshooting on http://www.ChicagoTech.net
How to Setup Windows, Network, VPN & Remote Access on http://www.HowToNetworking.com
I am having difficulty when trying to authenticate to the VPN server we have
configured.
I have configured the required Remote Access Policy in RRAS; I try to
connect each time and I get " Verifying username and password", but I am
never authenticated and the VPN connection never establishes.
The Server Status in RRAS is UP. The PPTP and L2TP ports all show Inactive.
I have "Grant Access" selected in the Remote Access Policy.
Any suggestions would be welcome.
Thank You.
 
Yes, PPTP does need GRE.

VPN Setup
A: PPTP VPN uses TCP Port 1723, IP Protocol 47 (GRE); L2TP: UDP Port 1701; IPSec:
UDP Port 500, Pass IP protocol 50 and 51. Note: 47 is a protocol number ....
www.chicagotech.net/vpnsetup.htm

ports for vpn
Don't have IP protocol 47 (GRE) Port 42 for name resolution. Don't have IP protocol
47 (GRE). A PPTP connection will fail if the firewall/router blocks GRE, ....
www.chicagotech.net/portsforvpn.htm


Bob Lin, MS-MVP, MCSE & CNE
Networking, Internet, Routing, VPN Troubleshooting on http://www.ChicagoTech.net
How to Setup Windows, Network, VPN & Remote Access on http://www.HowToNetworking.com
Please help me understand why. Does PPTP use GRE encapsulation??

Thanks Robert...

Kevin
 
A PPTP connection cannot work if GRE is blocked. PPTP only handles the
setup and maintenance of the tunnel. The actual data is encrypted and
encapsulated. The encapsulation uses a modified GRE header. If GRE is
blocked, no data is transferred and the connection closes.
 
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