Is there a way that I can schedule a weekly scan to start at a designated time?
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OK then select the scan that you want to schedule, avastUI > Security > Antivirus > Quick scan, etc. More details > Settings > Schedule.
I’m a little confused how to set the time. If I want it to run once a week at 8:00PM, how would I put the time in? BTW, thank you for the reply
see bottom of DavidR s picture… and try using 24 hour clock. 8pm should then be 20:00
Thank you for your reply. I entered 20:00 but it only shows 20:0, is that correct?
The input once entered as 20 : 00 and clicking OK resolves to 20 : 0 when you come back in; whilst it appears correct, it just doesn’t look right. I tested it and if you set it to 20 : 01 when clicking OK that resolves to 20 : 1, so it seems it removes insignificant zeros.
You could set it to 20 : 10 which remains as 20 : 10 when resolved.
Thank you David!!! 
No problem, glad I could help.