Why can’t I activate Windows on Server 2025 standard core edition?

I have a Windows Server 2025 Standard Core (The version without GUI) evaluation VM in Hyper-V and I want to activate it using my Server 2025 Standard product key.

First I tried it via the sconfig GUI but that errors out with code 0xC004F069 (more info about this code below).

Then I tried to use DISM /online /Set-Edition:ServerStandardCor /ProductKey:.... /AcceptEula but this prints me this error:

Version: 10.0.26100.5074

Image Version: 10.0.26100.32522

Starting to update components...
Starting to install product key...
Finished installing product key.

Finished updating components.

Starting to apply edition-specific settings...

Error: 1168

An error occurred while applying target edition component settings. The upgrade cannot proceed.

For more information, review the log file.

The logfile states Failed to copy license file for edition. Thread for Installing EULA Failed. Failed to apply edition settings. Failed to apply edition settings for [ServerStandardCor].

I also run DISM /online /Get-CurrentEdition => ServerStandardEvalCor and checked with DISM /online /Get-TargetEditions that should give me a list of editions I can upgrade to => ServerTurbuneCor & ServerDatacenterCor.
I don’t know why there is no standard edition listed..

I also tried to activate Windows via slmgr.vbs /ipk xxxxx-xxxxx-.... but that errors out with error code 0xC004F069 and that seems like I try to activate a key for the wrong edition and also that no system SKU was found. Running msinfo32 does tell me that there is no system SKU.

I have also read that I could try to take a Windows KMS key and apply that just for the version change but those also don’t work.

I don’t know what else I can try to activate Windows.


Edit: I just installed another VM with the same ISO but chose the edition with the GUI and on this machine I can successfully activate the Windows key. Even DISM /online /Get-TargetEditions does show me 3 targets, ServerStandard included. Why can’t I do the same on the version without GUI?