LrC (v13.5) won't open - Windows 11

If you get an error message? If yes, please post the message word-by-word.

What has been changed on your system before the issue occur?

Try to switch off the GPU support from the Lightroom preferences and check if that helps to fix the issue.

If Lightroom doesn't start correctly the please see "Solution 2" in the document behind the link below.

Troubleshoot GPU issues | Lightroom Classic (adobe.com)

In next step try to reset the preferences to the default settings by doing the following steps:

• Close Lightroom.
• Hold down [Alt]+[Shift] while restarting Lightroom.
• Overwrite the Preferences when prompted by the dialog.
• Close Lightroom.
• Restart Lightroom.

It's recommended to backup your preferences before you reset the preferences to the default settings: 

https://helpx.adobe.com/lightroom-classic/kb/preference-file-and-other-file-locations.html

If this doesn't help try to open another catalog or create a new one. Hold the Ctrl-Key while starting LrC. This opens a catalog selection dialog. In this dialig change to another catalog or create a new one and see if this catalog then works. You could then try to import your current catalog into the new one.