Can't establish VPN on windows client to OSX server

Hi everyone,

I'm stuck for a while now with a very annoying problem.

I can't establish a VPN connection on a windows client to a OSX Server. It worked fine while we had OSX server 10.6.

We recently updated to 10.8 and got this problem.

I know some of u are now thinking, the solution is: Just don't use windows... But the director of the company i am doing this for

doesn't want to switch to mac.

Also, this problem maybe be related to windows but i hope someone here can help me.

Things i've done:

I've tried PPTP ( didn't work either )

I've tried different users

I've tried adding a rule te regedit in windows ( according to a windows vista kb file for VPN trough NAT devices )

I've tried different authentication rules

In VPN log is Server admin everything goes well until:

pppd[87435]: fatal signal 6

vpnd[104]: --> Client with address 192.168.0.24 has hungup

after this it goes further with some successes.

I hope someone here knows the solution!

Thanks in advance,

Remy

Mac mini server, 10.8.5

server admin 2

( client ) windows 7 & 8

ps. sorry for my bad grammer, i'm dutch..