Can someone explain to me, how i delete the User Synchronsation on the Desktop App?
If i delete the App and reinstall, the Synchronsation Account is still in the Settings activated and we see all the Notes from this Account
If you want to completely delete the Joplin data and settings for a user on this computer you can delete their joplin-desktop folder.
C:\users\<username>\.config\joplin-desktop
If you run Joplin after doing this it will create a new joplin-desktop folder and Joplin will only contain the default notes, all settings will be the default, there will be no plugins apart from those "built-in", there will be no active sync settings. Joplin will be as if freshly installed for the first time.