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VPN Error 721, SBS 2003, XP Pro problem

Hi All,

I have an SBS 2003 server set up with a VPN

I can connect from 4 machines extrenally with no problems and can browse the network as expected. 2 of these machines are using DG834G Routers to connect, one is using an IPCOP firewall and the other is using a custom linux IPTABLES firewall.

The SBS 2003 machine is connected to the internet using a DG814 DSL Gateway with port 1723 forwarded to the SBS box.

I'm using the most up to date firmware on the DG814 (4.10) which claims to support VPN PPTP Passthru, however I can't find an option to enable / disable on the router itself, nor can i enable IP protocol 47, although I'm fairly sure this is working as the other 4 machines can connect with no problems.

On the 5th Machine I'm getting "error 721: the remote machine did not respond"
this machine is running XP Pro SP2, connected via a DG834G router.

Please advise!

2 Solutions
Check with the internet provider of the 5th pc if there is no filter on the line which block's incomming traffic like 1723.
Disable the XP SP2 Firewall just for test to see if this one doen't cause the problem.
bobalobAuthor Commented:
The 5th PC is a client, this PC is using the same ISP as one of the other machines with the same router, so I don't think that there is a filter on the line.

Have tried disabling the XP Firewall with no joy, I've also tried using DMZ on both server and client routers.
Hmm... maybe check that you have RRAS setup to allow enough incoming connections?

Are you trying to connect two PCs behind the SAME router, ie sharing an internet connection?
This very rarely works for me, most routers seem to be able to only forward one VPN connection to a particular server at a time. If this is the case, look at getting a router than can do the VPN connecting itself.
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bobalobAuthor Commented:
RRAS should easily be able to cope with the ammount of connections... I've had the server empty, and with other users connected when trying to connect this machine...

There are 20 IPs in the IP assignment section so that should be enough! I've tried with DHCP too, which works exactly as it's set up now. I've even tried changing the IP range the server gives out, which has no effect!

It's bizzare! if the router server end did not support protocol 47, would any of the machines be able to connect?

All PCs have seperate internet connections, so thats not an issue...
Try looking in the event logs for anything relevant?
Also, see this Microsoft KB article:
bobalobAuthor Commented:
nothing for RRAS in the event viewer!

the KB article you show is for L2TP, im using PPTP

Oops, didn't look too close at the KB doc.
Try connecting the client to some other VPN.
Found one here that I could connect to, (got wrong username/password though, obviously!)
bobalobAuthor Commented:

i'll set up an incoming connection on another box... will post back here once i've tried it...

we've got a few things to try tomorrow, he has a win98 box behind the same router so going to try and connect using that, also going to upgrade the router firmware at his end...
bobalobAuthor Commented:
upgraded the firmware on his router, reset it to defaults and it's all working now... thanks for your help guys...
which firmware did work for you? I tried both 1.05 and 1.04 with no success. Thanks for answer.

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