Hello,
Q1: Is the upgrade only possible if I do a clean install on my device?
Yes, you are correct. Windows Server 2022 21H2 is part of the Long-Term Servicing Channel (LTSC), while 22H2 and 23H2 are part of the Annual Channel. Because they are different servicing channels, an in-place upgrade from 21H2 to 22H2 or 23H2 is not supported. You would need to perform a clean install to move to 22H2 or 23H2.
Q2: Was the upgrade to 22h2 not a proper upgrade?
Yes, if you are using Windows Server 2022 21H2 edition, you cannot upgrade to 22H2 by installing a patch because it is a different product. You'll need to back up your data and settings before doing a clean install.
Have a nice day.
Best Regards,
Hania Lian
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