Update crashed EM client - now error 2755

Alas the update crashed EMClient & made it unloadable (error code too long to reproduce & lost now anyway), Uninstalled & tried to reinstall from scratch & now get error 2755 - any ideas anyone?
Failing that I still have database file - is it any use WITTHOUT EM Client?

Uninstall eM Client, then delete the C:\Program Files (x86)\eM Client\ folder if it exists.

Download and install eM Client from the latest version in the Release History

Exact the same problem here! Update good working program after receiving updatenote. Now unable to use or to reinstall. errorcode 2753. Unusable new installation at all!

Thanks that worked (though also had to change to run as admin, though I guess that’s a Win10 thing)

Also here thanks , all removed and installed new version 8.1.979.0 flawless.
FYI I made a photo copy of the failure notice: IMG_20210113_165108074

All works fine again!

Yes, I had that problem with some versions of 8.1. Usually you only need to run as Administrator once, after that you can start eM Client as normal.