Windows 10: Defender not Running Regular Scan

I was going to respond to your earlier post that I think what you are (were) seeing is the Automatic Maintenance Quick Scan. Especially if the time is so far off from when your scheduled scan is set. What does your Task Scheduler show for the scheduled task? I am guessing it will show (0x2).

I have the Automatic Maintenance Quick Scan disabled so I know that what is being reported (or not reported) is for my scheduled Quick Scan.

 

Is this what I want to look at?









Funny enough it shows 0x0 today. I wonder if the update that came through last night had anything to do with that?

 

What you are looking at is the Automatic Maintenance Defender scan. Did you create a separate task for a scheduled scan? If so it has to be created on its own, not within Microsoft>Windows Defender. As I said I have the Auto Maintenance scan disabled since the conditions for it to run are too restrictive imo. Computer has to be idle and untouched.

 

But *I* am the author of this scheduled scan.

 

Those four tasks are definitely part of Auto Maintenance. Looks to me like you modified the Windows Defender Scheduled Scan. You added a specific trigger, 12:00 PM. I would delete the trigger. On MS Answers someone who has some good knowledge said not to mess with the built in scan other than disabling it. You can try to create a new scheduled task for a Quick Scan or just let Auto Maintenance do it since your computer apparently meets the criteria it needs to run.

 

Yep bru is right. I did change the automatic maintenance scan by adding a trigger. I just deleted the trigger and lo and behold the scan ran by itself.
Lesson learnt; don't touch the Auto Maintenance setup. If you want to set up a scan, then do it somewhere else.

 

Yeah, I think you're right - that's what I did.

Edit: It's been a while, but I think I did that, because it never ran!

 

Things got a bit muddled in this thread. As long as the task has not been altered the Quick Scan that is part of Automatic Maintenance should run as long as your computer meets the criteria it needs. Namely being idle and untouched.

What isn't working is a separate Quick Scan that is created as an independent task. Since the AU I can with 100% confidence say that something changed which doesn't allow the created Quick Scan to run as it should. All three of my computers that do not have the AU (still wondering when they will get it but that's another discussion) run the scheduled Quick Scan without issue at the scheduled time. Or if the scheduled time is missed the QS will run as soon as possible. The one computer with the AU does not run the scheduled Quick Scan. Its Last Run Result reports as (0x2). I have been able to jump start it by opening Defender when the scan is supposed to run, but by no means is that correct.

If anyone has created a separate task for a Defender scan and is finding otherwise I would appreciate hearing it.

 

Hello, I am new to this forum and it helped me a lot.
So I want, perhaps, help you with this issue. The only thing I did was changing the user to run the task as a local user, not "SYSTEM".
This worked for me, even setting a custom scheduled job.





Sorry, text in picture is in dutch. Use the same places in yours.

 

I believe you are showing the scan that is part of Automatic Maintenance. For that mine is already set to System by default. Although I do not have anything listed for author. If the scan is running for you I think that is because it is the Automatic Maintenance scan.

 

@bru
That's correct. Default is System user. When set to System it will scan only ones then never again.
I changed it to a local user and now it will scan when the system is idle.
The author is by default empty. I had to recreate the task, because I by accident deleted the task.

 

@pcmb8866
Is Defender still scanning daily via automatic maintenance?

Would you mind posting a screen shot of 'Action' (Acties) tab in your scheduled Task?

 

I've never understood the need some people feel to set up a scheduled task to run a Defender scan. For the past year the automatic maintenance has run Defender scans for me.

That is, until the Anniversary Upgrade - it broke something and Defender never ran another scan. It finally alerted me that a scan was long overdue. I followed the suggestion on another thread...
Windows Defender No Longer Performs AutoScan
...and the automatic maintenance scans are back to running regularly again.

 

The criteria for Defender to run a scan as part of Automatic Maintenance are clear. And restrictive. I like to use my computer. If Defender has started a scan as part of maintenance, touching the computer will stop it. The scan will not be considered complete even if it was one second away from the end. Defender needs the computer to be idle for the scan to run. I like my computer to go to sleep after non activity. I don't like to waste energy by leaving a computer on and untouched waiting for a scan to start.

If Defender as part of Automatic Maintenance works for you that's great but don't think there aren't reasons some would want to have the scan run when they want.

 

Update

Automatic maintenance scan for Defender has not run since my OP. Just checked now and it has run? I have changed nothing.
Will it run tomorrow? Who knows?
Go figure.