[fitter]

Hi all.

Not always, but very often, when I'm browsing a folder within Windows Explorer a strange thing happens:
it goes selecting a file in the folder and "locks" the selection upon it, so that I can't select different files but only a set including the "selection-locked" file. To explain myself better, if I click in a white area of the screen, far from the files of the folder, to get the selection off, nothing happens, the selection remains!
The same thing happens also when I'm writing a document with Word: at a sudden it "sticks" a selection on a point of the text, that is a position between two letters, and it expands the selection as I move the cursor away from the sticked point. If I click outside the selected text, the selection doesn't go off!
The problem doesn't show in every application I'm using: for example, just few minutes ago it was annoying me while browsing files, but I could write this message (the one you are reading just now) without any difficulty.

Do you think it might be malware?

My OS is XP and I'm using:
>Zonealarm
>Spybot (updated; scan: no threats)
>AVG (updated; scan: no threats).

Really thanks for any suggestion.
Bye