This problem has been around since last September. Dont waste your time looking on Microsoft's sites for solution.
This worked for me:
1. Go to Widows Security Center, select Windows Update from lefthand pane area.
2. View your update history by clicking on underlined "view update history" . Check how recent you have been getting auto updates - you may find that you have not been getting them for some time, even if you have auto update selected.
3. Select change settings from the lefthand pane.
4. Select Never check for updates and uncheck all check boxes. Note that if you have Microsofts update service checked you will have to go back and re-activate it later to get back its check box.
5. Select OK to OK all the changes - this will turn off all auto updates.
6. Exit out of the Windows security Center. Have a cup of coffee. Then Go back to the Windows Security Center and check for updates (you have to be online). You will no doubt find that you have several - I had 9 - updates that were never automatically downloaded, including the latest Defender update.
7. Update your computer, then go back and re-enstate auto updating in reverse of steps 1-4.
I dont know if you will have to continue to do this every time the problem re-occurs. Maybe Microsoft will acknowldge the problem by then...
Good luck.
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