We have always recommended the supervised use of ComboxFix. The tool displays a disclaimer stating it should never be used in an unsupervised environment. See "ComboFix Usage" at BleepingComputer.
Only one of the reasons it should also be used in conjunction with those who are in contact with its developer:
This morning it was discovered ComboFix had a file in it that is infected with the Sality virus. Please read:
"Information about ComboFix being infected and what you should do"
'Unfortunately it has come to light that the program ComboFix had a file in it that is infected with the Sality virus. The minute we heard about this, we pulled the executable so that it is no longer available from BleepingComputer.com. Unfortunately we have no control over other sites that may have mirrored ComboFix without permission, so please do not attempt to download it elsewhere.'
Continued here: http://www.bleepingcomputer.com/forums/topic483431.html
Carol

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