Trojans



I have had in the past on my laptop three different Trojans (all the WIN 32
varieties). With the help of the experts from this very useful Newsgroup I
have been able to remove them.

As I have been unable to set up the free version of Avast to automatically
perform a daily schedule to run a scan, I run a scan once a week manually.

My question is, if one of these Trojans has been on my PC for a week before
being detected what kind of damage may it have done to my computer. When I
did a search to find out what kind of problems they may cause (so could not
be on the look out for specific kinds of behaviours) I could not find any
information. So once this has happened can you ever be certain your PC has
not been compromised and is clean? The only change I seem to notice
recently is a slight slow down in operation, but then it could be my
imagination.

TIA

B.W.


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