I would follow Grif's advice here;
I hope that helps.
I'm infected with one of those rogue spyware programs that tries to scam you into buying virus protection, but this one is different. It has blocked all programs that attempt to scan the computer with a "Windows cannot access the specified device..." error and has also blocked Windows Installer. They are even blocked in safe mode. It has also disallowed any System Restore points other than the one it set up itself. These problems keep me from using the regular solutions to remove it. What can I do?