Return of the BIOS trojans
The next time Windows launches, the malicious code downloads a rootkit to prevent the drive's MBR from being cleaned by a virus scanner. But even if the drive is cleaned, the whole infection routine is repeated the next time the BIOS module is booted. Mebromi can also survive a change of hard drive. If the computer doesn't use an Award BIOS, the contaminant simply infects the MBR.
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