I had an issue on a friends computer that had Rootkit maleware/virus and this was the only thingthat was able to remove it without reformatting.
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Hitman Pro 3.5.4.85
Recognizes and removes
viruses, Trojan horses, rootkits, spyware and other malware.
Revolutionary innovation in scan technique to distinguish malicious and safe software without signatures.
Short scan time - searches the system within a few minutes.
No extra system load.
Impossible to make false positives on important systems files thanks to "profiling" and whitelisting.
Multi-vendor identification of malware in our real-time "Scan Cloud".
Automatically restores common system alterations made by malicious software.
Creates a check point in
System Restore before removing malicious software.
Removes resistant threats using native NT boot-time deleter.
Removes references to malicious software (like shortcuts and registry entries).
Free malware scan.
Free online support in English, German and Dutch.