I'm running XP Pro SP2 with a DSL modem connected to my PC via ethernet card and another ethernet card to connect to my xbox 360 and also a PCI wireless access point card with antenna to give internet access to another remote PC. Everythings been fine and dandy but about a day ago somethings been acting all whacky. Now at random times the whole network/internet goes down and I've narrowed it down to a few things. I can tell that the Internet Connection Sharing/Firewall service somehow gets shut down and I would have to restart in order for the everything to go back up. I've run a barrage of scans for virus/spyware/trojan/etc with HiJackThis, Spybot and NOD32 anti-virus and everything is clean as usual. When I go to the Services windows and go to ICS/Firewall services I can see its stopped even though it usually is on on startup. When I try to start it I get this error "Could Not Start the Windows Firewall/Internet Connection Sharing (ICS) service on Local Computer. Error 5. Access Denied". I don't know if this is a result of some trojan that changed some settings in the registry.

Has anyone encountered problems like this before? Because its getting annoying to restart the computer every 10-15 minutes just to use the internet.

Thanks