nb1 writes:  

Windows has, for many years, come with a special mode you can load at boot called Safe Mode. The idea is that non-essential services and software don't load in safe mode and so it can be useful in diagnosing system problems.

You might assume that it can be useful in fixing malware infections and you'd be right, but not in all cases. As McAfee's Avert Labs points out in a blog entry, it's possible for malware to set itself up to load even in Safe Mode.

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