OK, after some hours of deinstalling, reinstalling, booting and trying out different BIOS settings, AHCI drivers and
dotnet versions (without any outcome…), I found out that I had the same “simple” problem as described in this thread:
After deleting a strange key with some abnormal symbol as key name in the registry under
the ExpressCache-GUI is working and I was able to activate the software.
There remain a few questions:
Where does this strange registry key comes from?
Why is it blocking the ExpressCache-GUI?
The ExpressCache-GUI seems to be not a “real” software, but some kind of InternetExplorer window
dependent on ActiveX-PlugIns and the funny IE security settings. I doubt that this can be called good
programming practice nowadays…