Linksys DSL Router

[Michael]

I've had a Linksys router setup with port forwarding
(1723 & 47) for about a year now without any problems
accessing Microsoft VPN through PPTP. The last couple of
days, I noticed that getting connected was intermittent.
Then it soon failed. So, I replaced the DSL Router with
another Linksys VPN Router and still cant get connected.
Currently I have removed the router and am connecting
straight through without any problems. However,
everytime I add the router I get error message 721.
Almost looks like its timing out.

Thanks in advance for any help.

 

[Bill Grant]

It isn't port 47 that is required, but GRE (Generic Routing
Encapsulation), which is IP protocol 47. The VPN data is encrypted and
encapsulated, and the packet has a GRE header. So the connection fails if
GRE is blocked. Depending on the router model, you may find GRE defined by
name or by protocol number, or it might just have something like PPTP
pass-through mode or VPN pass-through mode.

If it works OK on a straight-through connection, it must be the router
which is upsetting things, not the server itself.