After solving the issue reported by https://community.adobe.com/t5/framemaker-discussions/we-can-t-verify-your-subscription-status/td-p/... I decided to de-install Acrobat DC Reader, because I stated that I anyway most time need to use Acrobat 2017 Standard, which I also have installed.
However, since the removal of the cloud App Acrobat DC it was not possible to open Acrobat by double click on the PDF file. All links found to cure this problem propose the following :
However, after that procedure (even if selecting the application from the file location where it is installed) I still have “Opens with: Unknown application”. → Loop, endless.
So I dived into the Registry and found this: Although a directory
C:\Program Files\Adobe\Acrobat DC no more exist after de-installation of Acrobat DC I found many occurrences of the data string
C:\Program Files\Adobe\Acrobat DC\Acrobat\Acrobat.exe in the registry.
After deleting relevant keys the problem was solved: a double click on a PDF file opens Acrobat 2017 Standard as expected.
→ Obviously the de-installation of Acrobat DC was not complete.
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