Windows Server 2019 Essential - The product key entered does not work.

Copper Contributor

Hi, I created a VM and installed windows server 2019 Essentials Evaluation and after 3 months I decided to buy the original license (OEM).
Activation fails and generates an error message:
The product key entered does not work. Check it and try again or enter a different one (0xc0020036)
From cmd, it reports Error 87, Invalid Product Code KEy.
I tried these commands:
slmgr -ipk <KEY>
(0xc0020036) On a computer running a non-core edition of Microsft windows, run slui 0x02 0xC0020036 to view the error text. If I run the command it tells me "No Endpoint available in the endpoint mapping"

I tried to do these procedures but without success:

sfc / scannow
dism / online / cleanup-image / restorehealth

Also I have another problem but I don't know it is related, Windows update does not install the latest updates: KB4601345 (code error 0x800f0986), KB4601345 (code error 0x80070643)

Windows Server 2019 Essential is not a Domain Controller, there are no Antivirus and the only firewall is the Defender that I have also tried to disable.

What can I do to activate the license?

4 Replies
I'd ask the OEM provider's trained licensing specialist about this. Its possible the OEM product key is bound to specific OEM provided installation media.

Hi Patrick, thanks for the reply. I tried asking my provider, but he said he didn't know.
Well if it were me I guess I'd try to get a refund.


I might as well make a refund but it won't fix the problem. I need to activate my license. Do you think the product key is not really valid? It is not possible that there are various types of problems on the server Windows?Also I have another problem but I don't know it is related, Windows update does not install the latest updates: KB4601345 (code error 0x800f0986), KB4601345 (code error 0x80070643)