Vista & XP Gaming via router

Problem is that Vista and XP can't find each other when gaming vi
router. I tried to play Grand Prix 4 on LAN with TCP/IP but it doesn'
work. Vista finds session made with XP but cant connect. XP doesn't eve
find game made with Vista.

Computers finds each others at network places. They have same workgrou
and they share files and connections are ok. Weird is that i have
computers (Vista, XP, XP) connected to router and XP machines
multiplayer in Grand Prix 4 works fine. I just tried to connect Vist
& XP computers with cross-over cable and multiplayer worked fine! Look
like Vista can't communicate with XP via router

I also turned firewalls off but no help

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Jy1ppy