[Kees B]

.... I think he must have downloaded the full installation package, looking at the file size in his screenshot.

Aha, interesting. So you only had to execute ETKA_80_Install.exe (2192 kB), without a further download necessary in order to update from 7.5 to 8.

Then I guess my problem is that my existing (German version) ETKA 7.5 is not seen by the update installer. It therefore proceeds to download automatically the complete install file, which then apparently runs into the same issue.

So it is back to the original question: why does the updater not find the ETKA 7 installation on my system?