It is solved now. The problem wasn’t even the motherboard, which can also make big trouble. The problem was that Microsoft has invalidated the whole key. Seems that i have activated it one time too often, and so they became aware of it.
The microsoft tech support told me that it was a volume license key, not meant for single users. I bought the license from a license dealer here. I have contacted this license dealer now, and received a new key. Windows is unlocked again, and everything is running now. Let’s have a look how long this key works this time ^^
Ah, fun fun fun 😀
Oh, and it seems that i need a new printer too. HP smart requires a cloud account for the scanner now. No way …
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