Anti-Virus software is a necessary evil, even the best of them will cause some slowdown as each file you download or open is scanned for malicious intent, and if you have been unfortunate enough to purchase a commercial package or download AVG, you will know all too well the torment of a system scan in progress.
To this end, Avast AntiVirus always stood proud. Virus scans could be scheduled to scan your system whenever the screen saver was running. No inconvenience, and when you moved your mouse the scan stopped. A wonderful solution.
Recently Avast purchased AVG, it appears they got lumbered with the dumbest developers from the acquired company because the first update after the aquisition has resulted in the removal of the "special scan" which enable scanning when the screen saver is running.
If (like me) your avast has not yet updated, do not be surprised if when Avast updates your screen saver ceases to work. At this point you will need to change your screen saver so you are not left stairing at a blank screen.
The last version of Avast with the built in screen saver scanner is 12.3.2289, the next version is 17.1.2286 (this alone shows some level of stupidity has crept in, one can only assume that someone thinks it is important to have a version number greater than the version number of their arch rival which they recently purchased, why else would it jump from 12 to 17?)
My apologies for the inconvenience. If any company supports or introduces this wonderful feature in the future I will advise you so you can make the change if you wish.
I cannot understand why any company with a great product with one feature that stands above the crowd would choose to dumb itself down to the lowest common denominator - sad really.
In the interim though, fear not!! Avast AntiVirus is still a great program providing great protection (it is just missing it's best feature)