If Liquid Studio fails to uninstall either from an Auto Update or from Windows Control Panel, please re-run the old install for the exact version e.g. 19.x.x.x and it should allow you to uninstall the application.
If you login to our website, you can see all the old downloads here:

More Information

During installation, the Liquid Studio installer stores the Uninstall information in the registry:

On a 32 bit PC 'All Users' option:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Liquid Studio

On a 64 bit PC 'All Users' option:
HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Uninstall\Liquid Studio

On a 32 or 64 bit PC 'Just Me' option:
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Liquid Studio

If this registry entry is no longer available then the uninstall will fail.

Also, the Paths within these registry entries point to the previous install which is stored in the ProgramData folder on your PC. If the paths no longer exist, then Microsoft Windows Installer will not be able to invoke the Uninstall process.