The only way to proceed in that sort of situation is to boot from a known-good (non-infected) OS in order to scan, clean and then backup the data. This could be done by installing the drive in another system or booting the existing system from a different drive or bootable disc (such as the
UBCD4Win). I prefer to use another system since I can have the OS and tools of my choice ready to process the questionable drive as well as to have multiple docks for easily attaching the bad and backup drives. Scott.