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Q: Error 721 and error 800

I have SBS 2003 Standard Edition. The server has two nic's for NAT on the RRAS. One nic is for an External IP address of and the other nic is for an internal IP address of The router is a  Linksys WRT54G3 that gets the DHCP address resolved by TZO.com to a friendly name for all services to the IP address without any problems except the VPN connection. I keep getting errors:721, or 800 when attempting to connect with XP Professional machines. I have all of the following Ports forwarding to the External nic, these are the settings 25 SMTP TCP,80 http,110 pop3,443 https, 500 ipsec,1723 PPTP,3389 Terminal Services,4125 RWW. I double checked the check list in server management and enabled VPN to the appropriate users. I went into Server Management. I double checked the settings inside RRAS for the internal and external nics and the NAT/Firewall is showing SMTP, RDP, HTTPS, VPN PPTP, HTTP, RWW settings all checked on the external nic. When attempting with an domain administrator account I still get those error:721,and 800 . What am I doing wrong????? I greatly appreciate your assistance fixing this issue. Thank you.

A: Try connecting the actual IP address instead of the dns name for the VPN connection to see if it is a name resolution problem or not. It would also be best to try and use PPTP before attempting to use L2TP due to the complexity of L2TP working over NAT and requiring computer certificates for authentication. On a client computer, configure the VPN connection to use PPTP as the type of VPN under networking. Also make sure that any router/firewall in the VPN connection path is configured to allow protocol 47/GRE which commonly is referred to as PPTP pass through.  --- Steve

Reply: Thanks for the replies, I found out it was a bug in the Linksys WRT54GS routers firmware preventing the PPTP pass through. As soon as I flashed the firmware she worked. Thanks again.

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