I have set up a vpn server running on win2003, and everything works ok when I connect to it on the local network. But when I try to connect over the internet I get an error saying: Disconnected. Error:721: The Remote computer did not respond. I have a linksys BEFW11S4 Router, and I enabled the following in the settings: IPSec Passthrough, PPPoE Passthrough, and PPTP Passthrough. I also opened up tcp port 1723, but still its not working. Anyone have any ideas??
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VPN ok on internal but not external net
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John Lewis
Programmer
A 721 error can mean so many different things. A few places to look:
Check to see if the connection on port 1723 is getting through to your server. Look at the event log, you should see something.
Try a telent connection to port 1723 of the VPN server. Open a command prompt on a remote machine. Type 'telnet xxx.xxx.xxx.xxx 1723', replacing the xxx with the IP you are trying to connect to.
If you get a message that you are connected to the host, or a blank screen followed shortly by a "Connection to host lost", your connection to the server on port 1723 is fine, GRE (protocol 47 or pptp passthrough) is the issue.
If you see a "Connection refused" message, you have a firewall issue, either at the router or the server.
If you see "Connecting to xxx.xxx.xxx.xxx" for some time, followed by "Could not open connection . . . Connection failed", you have not gained anything as there are many causes possible.
Check your event viewer after the telent connection for new messages, as well.
One last note. Many Linksys routers have a problem with pptp connections. They report a 0 window size when presented with a request for a connection on port 1723. It has been an ongoing problem for some time. Some models have firmware fixes available, some do not. What really gets me is Linksys knows that this problem exists, yet many of their new routers ship with the problem. The only reliable way to verify this is to install a packet sniffer (I like ethereal) on the VPN client and watch the connection.
Check event viewer, try the telnet thing and post back.
Check to see if the connection on port 1723 is getting through to your server. Look at the event log, you should see something.
Try a telent connection to port 1723 of the VPN server. Open a command prompt on a remote machine. Type 'telnet xxx.xxx.xxx.xxx 1723', replacing the xxx with the IP you are trying to connect to.
If you get a message that you are connected to the host, or a blank screen followed shortly by a "Connection to host lost", your connection to the server on port 1723 is fine, GRE (protocol 47 or pptp passthrough) is the issue.
If you see a "Connection refused" message, you have a firewall issue, either at the router or the server.
If you see "Connecting to xxx.xxx.xxx.xxx" for some time, followed by "Could not open connection . . . Connection failed", you have not gained anything as there are many causes possible.
Check your event viewer after the telent connection for new messages, as well.
One last note. Many Linksys routers have a problem with pptp connections. They report a 0 window size when presented with a request for a connection on port 1723. It has been an ongoing problem for some time. Some models have firmware fixes available, some do not. What really gets me is Linksys knows that this problem exists, yet many of their new routers ship with the problem. The only reliable way to verify this is to install a packet sniffer (I like ethereal) on the VPN client and watch the connection.
Check event viewer, try the telnet thing and post back.
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I did a google search for it and came up with this:
I'm not sure how that was supposed to help, but it didn't. I guess I will give them a call on monday.
I'm not sure how that was supposed to help, but it didn't. I guess I will give them a call on monday.
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