With both boxes checked, 28 minutes. However, at some point around the 52% mark, my mouse stopped responding, Avast window stopped responding, for at least 2 minutes, then, boom, all of the sudden the scan window say's it finished. Also, during the 9% mark my mouse becomes almost completely unresponsive, the Avast window, while the timer moves, the tab buttons are not responsive and icons and such on my computer become unresponsive. So something is not right.