If your computer is turned off at the time of a scheduled scan, you can set to automatically make up a missed scan with a Quick :

1. Click , then Antivirus.
2. Switch on Catch Up Scans.

This will automatically make up a missed scheduled scan. This means, for example, that if you scheduled a scan for 1:00 a.m. and the computer was turned off for the night, once your computer is turned on will automatically begin a Quick Scan after a delay.