Windows 11 deactivated after 24h2 update

Had exactly the same issue with 10 Pro OEM licences that had been happily uplifted to Windows 11. On applying 24H2 they were complaining about not being activated and the "Enter Key" and "Troubleshoot" buttons in the licencing section did nothing. Resolution:

Admin Command prompt

• slmgr /ipk AAAAA-BBBBB-CCCCC-DDDDD-EEEEE {The Key from the sticker}
• (Should get a message box saying import successful)
• slmgr /ato
• (Message box saying activated successfully)

Right faff, but scriptable so not the end of the world. Not sure what's gone on with 24H2 but it feels like a bit of a train wreck all round....

I confirm - I have the same issue. I could not overcome that problem. I know my product key, but even though the activation could not succeed. I reverted to 23H2 and all is OK again. Of course, for now I postpone the update for 24H2.

How to revert?

Settings > Windows Update > Advanced options > Recovery > Go back.

It is appalling that this is still happening. Six weeks after this initial message, I have also updated with Windows 11 24H2 and face the same problem.

It's the first time I've had a problem with a Windows update, and I've been around a while, but surely this is going to be expensive for Microsoft?

David

I've got exact problem with activation my Windows 11 Pro after installing 24H2.

My license based on a previous Windows 7 or 8 licence with last characters T83GX

Why it happens? I'm also following Windows Insider program and got a lot of Beta versions of widows, but never got activation issues.
What should I do now to activate my Windows?

I finally found the correct key...I couldn't see it as it was buried under cables and computer stuff...after a couple of goes at copying it correctly I activated windows...apologies for mucking you about....

cheers

col