|If you look around these forums McAfee gets a poor rating.|
If you should decide to run with any of the products mentioned be aware that there is no harm having other products around as long as they are simply for scanning in the event of a suspected infection. Two or more programs running in the background can cause conflits.
Two that spring to mind are:
MalwareBytes, which has a good record of finding and fixing things that AV's miss. The free version is fine and you just keep it updated and scan when required.
SpywareBlaster (free) is also worth considering. This doesn't run at all but puts kill bits in the registry to prevent access to various known nasties. It just needs to be updated about once a fortnight, that's all.
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