I have a Windows 7 Ultimate box that was infected with cutwail and possibly sirefef. I successfully removed cutwail, but attempting to remove the other infections was impossible. Running RKill would result in the immediate "Windows has encountered a critical error ..." messagebox and restart the computer a minute later. Now, every time I start up, I receive that message after about a minute, and a reboot. Further, this morning when I booted up, Windows complained of a corrupt winload. Two rounds through Startup Repair did fix it, but the reboot issue remains. I'm sure that there are either infections remaining, system files that have been damage by the virus(es), or both. System Restore cannot complete, and Startup Repair. Please advise on how to fix this, and thanks very much for the help.