VPN with Microsoft Routing and Remote Access

[Guest]

I have a user that receives a RAS error 721 on his Windows XP laptop and on
the Windows Server 2003 an event ID of 20209. I followed the registry fix
from Microsoft KB article 810839 without any success. I can connect to the
VPN with my laptop. I contacted his ISP and they will not give technical
support with VPNs. How do I test to see if the ISP is blocking Generic
Routing Encapsulation (GRE) protocol packets? Does anyone have any
suggestions to resolve this issue?

Thanks

 

[Robert L [MS-MVP]]

This like may help. But it tests between VPN server and client. However, if one client to server work fine, another other client should work.

How to test GRE nd PPTP How to test GRE and PPTP using PPTPsrv and PPTPclnt. PPTP VPN tunnel requires that the both VPN server and client opening TCP port 1723 and IP protocol 4. ...
www.howtonetworking.com/Tools/testgre.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
I have a user that receives a RAS error 721 on his Windows XP laptop and on
the Windows Server 2003 an event ID of 20209. I followed the registry fix
from Microsoft KB article 810839 without any success. I can connect to the
VPN with my laptop. I contacted his ISP and they will not give technical
support with VPNs. How do I test to see if the ISP is blocking Generic
Routing Encapsulation (GRE) protocol packets? Does anyone have any
suggestions to resolve this issue?

Thanks