One of our clients recently opened an out-of-state branch office with three workstations. We set up a Netgear ProSafe FVG318 VPN Firewall and shipped it to them (we're *not* using the built-in VPN functionality on the router). Walking them through set up was uneventful, and internet works fine through the router. One person at the new branch uses a built-in Windows VPN connection back to a server running 2003 with RAS at the home office. Lots of this client's employees are using a Windows VPN with no problem, but the user at this new branch said she is intermittently disconnected from the VPN 5-6 times throughout the day.
Additionally, last week a couple of the execs visited the branch and wanted to connect to the VPN but they discovered only one person could be connected from that location at a time. I've tested this and verified that's the case. Using different user names on different computers, only one can connect at a time.
When the second person attempts to connect, they stay at "Verifying username and password..." for about 25 seconds and then receive Error 721: "Disconnected" (see attached). In the server Event Log, event ID 20209 shows up (see attached):
A connection between the VPN server and the VPN client XXX.XXX.XXX.XX has been established, but the VPN connection cannot be completed. The most common cause for this is that a firewall or router between the VPN server and the VPN client is not configured to allow Generic Routing Encapsulation (GRE) packets (protocol 47). Verify that the firewalls and routers between your VPN server and the Internet allow GRE packets. Make sure the firewalls and routers on the user's network are also configured to allow GRE packets. If the problem persists, have the user contact the Internet service provider (ISP) to determine whether the ISP might be blocking GRE packets.
i have gone through all the FVG318 settings and everything checks out from what I can tell. The MTU size is at the default of 1500, the inbound and outbound rules are set to allow all possible VPN traffic, all the VPN pass-through boxes are checked. I also did the most recent firmware update to the firewall but the symptoms I described don't change.
I've been unable to find any documtation related to being able to establish only one VPN connection at a time behind a given firewall. Any help is greatly appreciated.