VPN - can ping remote host, not other servers on remote network

[jakusb]

Hi,

I have a frustrating problem related to VPN function of Teamviewer.
I am able to ping the remote host (running Teamviewer VPN), but unable to ping any other server on remote network.
I use a Windows 7 laptop to connect to a Windows XP instance.
After adding routes both ways, I can ping both remote servers.
From winXP to Windows7 I can see rest of network and ping any other server, although sometimes I have to first ping 192.168.1.1 (router to internet on one end) before I can ping 192.168.1.112 (nas server, not teamviewer instance).
Form Windows7 to winXP I can only ping the remote server, but none of the other servers on that end.
I enabled IPRoutingEnabled on both ends.

Seperately I tested a situation with 2 WinXP instances connecting via Teamviewer VPN. Both servers were unable to ping other servers. Hence my current suspicion that problem is on WinXP side...

I used WireShark on both ends to trace the ping command. I saw the request arriving on remote TeamViewerserver, but no response given...

I hhave been working on this problem for several days, searched the internet in all possible ways, but no solution. I did find a number of similiar reports, but none with a solution.. I getting desperate....

All help and suggestion are very welcome!

[jakusb]

Ok, part of the problem seems fixed now.
I figured out that some devices do and others don't automatically ping correctly.
I had to add another route to one of the devices so the ping could find it's way 'home'.
Now I wonder... Why do some devices automatically figure this out and others require an explicit route?