Have recently installed Vista Ultimate x64 and got most of it setup how I want now. However I am having problems with getting Valves Steam Client to connect to the authentication servers which in turn means I cannot join games servers :( I've run the steam connection test and all ports pass. I have turned off the Windows firewall and also specifically disabled on the network connection. I have tried running in compatabilty mode aswell (XP). I have searched the web for similar issues but to no avail, I guess because bugger all gamers actually have Vista yet. My PC is connected to a domain and connects to the internet through ISA Server 2006 Standard which limits both outgoing and incoming traffic. I know the rules are right because a) It worked fine when the machine was XP and b)It works from my 2003 and other XP machine on the same domain. My mate has Vista and has no problems :E Incase it helps the full specs of my machine is: nForce4 based mobo AMD X2 3800 2GB Corsair DDR400 GeForce 6800GT 256MB SoundBlaster X-Fi 64MB 1TB Spanned Disks This spec scores a 4.8 in the performance rating. Of course Valve do not support Steam on the Vista OS, so it maybe that it just will not work until maybe an update, would be intresting to know if other people have come accross the issue, or a similar problem. Ta