Error 721 on VPN remote access

[Neil Hoffman]

I set up a W2K3 server as a VPN server, and I can not get past
"verifying username and password" when I try to connect from a remote
client. This is all being done within my LAN. The server has one NIC
and NAT is not enabled. There are no routers or firewalls between the
client and the server, just two switches. Any ideas?

Thanks.

 

[Robert L [MS-MVP]]

Use pptpsrv and pptpclnt to test it.

How to test GRE and PPTP using PPTPsrv and PPTPclnt
http://www.chicagotech.net/vpnissues/vpntools.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 set up a W2K3 server as a VPN server, and I can not get past
"verifying username and password" when I try to connect from a remote
client. This is all being done within my LAN. The server has one NIC
and NAT is not enabled. There are no routers or firewalls between the
client and the server, just two switches. Any ideas?

Thanks.

 

[Neil Hoffman]

I used pptpsrv and pptpclnt. The results are below. It appears to be
working, except that there is an error message from pptpsrv:
"Error 10048 binding Socket:
WSAEADDRINUSE: Address already in use
I tried my VPN connection again and it is still not working.

pptpclnt 192.168.0.10

Initializing WinSock...
Obtaining host information...
Successfully resolved server's host information

======================================
Enter data to send to server (between 1 and 255 chrs.), then hit
enter:
-->asdf

Successfully connected to server using TCP port 1723 (PPTP)
Sending data to server

Waiting for a reply to the data which was just sent...
Received a reply. Reply contains the following text:
--->

=================================
Connectivity test to TCP Port 1723 was successful!!!
Closing down socket...
=================================

Creating a socket to test GRE protocol traffic...

Total GRE packets sent = 1
Total GRE packets sent = 2
Total GRE packets sent = 3
Total GRE packets sent = 4
Total GRE packets sent = 5

=====================================
Check server to see if the GRE packets were received successfully
=====================================

Closing down socket

Goodbye!


pptpsrv

Error 10048 binding Socket:
WSAEADDRINUSE: Address already in use

Created socket for GRE protocol test

Listening on PROTOCOL 47 for incoming GRE packets...

Total GRE packets received = 1
Total GRE packets received = 2
Total GRE packets received = 3
Total GRE packets received = 4
Total GRE packets received = 5

======================================
GRE protocol test was successful!
======================================

Closing socket

Goodbye!

 

[Neil Hoffman]

One more bit of info. If I netstat on the server while the client is
waiting ("verifying username and password"), I see an entry for the
pptp connection with the local address "mainserverptp." Once the
client gets the error 721 message, that entry goes away.