Windows 10: Windows Defender Offline Scan Not Working - and Not Even Microsoft Support Can Fix It

First time poster.Running Windows 10 Home on a 9 year old HP Pavilion Desktop. Build 21H2.Use Windows Defender as only malware protection. Everything great until two days ago when notified of a threat.Took action and threat removed.Further notified to run Windows Defender Offline Scan.Scan started and computer restarted but immediately shutdown.Read all the posts I could find.Did sfc /scannow.Reinstalled suggested .dll files.Did DISM scanhealth checkhealth restorehealth.No change.Called Microsoft Support.Level 1 does all the above again by remote session.Level 2 convinces me to do Repair Insta

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Microsoft Defender Offline Scan

I'll give this thread a little bump and explain what I have tried so far to no avail. After hours of extensive reading about how WDO and now Microsoft Defender Offline scans are not working for some since as far back as 2017 for Windows Defender Offline, I had removed all remnants of Malwarebytes from my registry in an attempt to see if any of those entries were conflicting with the Microsoft Defender Offline Scan.

No dice!

The second thing I tried was a Restore Health function with the DISM command and it reported a successful operation and still the Offline scan won't initiate. Yes, I rebooted after the DISM Restore Health Command.

No Dice gain!

Some articles suggested a repair install; but honestly at this point, if sfc /scannow isn't flagging anything and my OS is completely operational with no Event Viewer Errors and no Reliability History issues of any kind (especially Critical Events) I really can't justify using a repair install that probably will not fix it either.

I mean I literally have no indication that any corruption exists anywhere throughout the OS; yet something that worked before the Cumulative Update is now broken and not a peep of it has been mentioned in any documentation that I came across lately that it is a known issue with the November 11th Cumulative Update for systems on 20H2.

Sure I could restore a full backup image I have to prove that Microsoft Defender Offline Scan worked prior to the update; but who would really be interested in that proof?

I don't understand why this feature was broke on some systems since 2017 and mine remained immune until just now.

So I would really like to hear suggestions if anyone knows how to get this feature working again on this latest Version and Build listed under my Avatar.

Thanks to any and all who have knowledge about how to fix this or if they heard a rumor that this is another feature that is being done away with and I just haven't heard yet.

 

Microsoft Defender Offline Scan

Restored the Macrium Image and got my Recovery partitions back:






So as expected, I had a bunch of updates to do:





After the updates, I gave Microsoft Defender Offline a try and it worked!









And this just shows that I'm back at the latest version build of 20H2:





This one was my fault and I admit I was the culprit of my own troubles. It was just a coincidence that I used Partition Wizard around the same time the Cumulative Updates were going on from Oct 28th to November 11th and it gave me the suspicion to suspect them being responsible for the Offline scan problem.

I mean who the heck would of ever thought that a Recovery Partition would have anything to do with an Offline Scan in an Online world?

A special thanks to OldNavyGuy for his suggestion that a Windows Recovery Partition being deleted was the problem.

 

Microsoft Defender Offline Scan

The same thing happened to me...because I deleted the Recovery Partition on one of our systems.

That also broke Reset this PC in Settings > Update & Security > Recovery

I tricked myself into thinking that the space was up for grabs -





Uh...no -

(Note: MiniTool Partition Wizard calls Disk Management "Disk 0" - "Disk 1")