There is an ongoing trend of software, especially antivirus, to be less and less controllable by user, probably supposing that the users' intelligence is lower than that of the software. For example, some 10 years ago (approx.) AVG Free allowed the user to switch off the resident feature and use it just for scanning, or to exit it completely. Later on, it was impossible. If you wanted to stop the protection (= overhead of scanning & updates) for particular moment, you had to uninstall it!
Does there exist any free antivirus software that is controllable by user? I'm using Windows XP.
I have tried AVG Free and Avast several years ago (situation might have changed since, though its unlikely) and was dissapointed in such a way that I completely refrained from using antivirus.