it does not start (open) anymore.
It would be good If i could have known what "did not start (open)" means. Double clicking on the icon or selecting in the Start menu results in ... nothing? But...

The running as Administrator has probably scorched all of the settings. The ACP installer has build-in repair logic for running as Administrator etc. Did you do your uninstall/reinstall cycle "as Administrator"? If so I may need to get on and try to see what's going on as virtualization or not can cause havoc.

Try this first: Run the ACP installer, not as Admin, once. Don't uninstall. Now try to start ACP. If that doesn't work I will need to log into your system via remote assistance and see what has been damaged and try to fix it. Don't worry I don't mind at all!!