VPN hanging on verifiying username and password

[Marc]

I setup VPN on WIndows 2003 server. When I click on the
VPN link on the client, I enter the credentials and click
connect It sits at verifying username and password for a
minutes then fails. I know the credentials are correct.


The error massage is

Error 721 : the remote computer did not respnd. blabla


Any ideas

 

[eddiec]

check event viewer. you may have enabled L2TP ports and have no certificate

 

[Bill Grant]

Where is the client? Routers/firewalls can block GRE (ip protocol 47),
which prevents a PPTP connection and gives you error 721.

Can you make a VPN connection from a client on the local LAN?

 

[Guest]

I have same issue, my vpn works for a while then for whatever reason stop working.... on the LAN client connects with no problem, but when trying thru firewall it hangs the error 721, what am finding is that if I use telnet x.x.x.x 1723 command I can connect, but when I use telnet x.x.x.x 47 I cannot ..... am wondering there is some sort of problem with firewall redirection... although I have a rule wher port 47 is allow and redirected to ras it does not work but it did before... any sugestions... in addition to that I just installed new ras server and changed 1723 and 47 redirection to new IP on the lan still nothing.... and one more info I have pool of modems attached to ras and do not have any problem to dial in which is telling me I have an issue with firewall..... anyone

Tx

 

[Bill Grant]

Port 47 is not required for a PPTP connection. This is a myth, caused by
someone misreading the documentation. What is required is GRE (Generic
Routing Protocol). GRE is a protocol, not a port. It is IP protocol 47
(hence the confusion with port 47).

If any router/firewall in the path blocks GRE, the connection fails with
an error 721. The reason is that the encrypted data travels inside a packet
with a GRE header. If GRE is blocked, no data is transferred.

I have same issue, my vpn works for a while then for whatever reason stop

working.... on the LAN client connects with no problem, but when trying thru
firewall it hangs the error 721, what am finding is that if I use telnet
x.x.x.x 1723 command I can connect, but when I use telnet x.x.x.x 47 I
cannot ..... am wondering there is some sort of problem with firewall
redirection... although I have a rule wher port 47 is allow and redirected
to ras it does not work but it did before... any sugestions... in addition
to that I just installed new ras server and changed 1723 and 47 redirection
to new IP on the lan still nothing.... and one more info I have pool of
modems attached to ras and do not have any problem to dial in which is
telling me I have an issue with firewall..... anyone?