V6.0 Crashes on Opening

I updated Adobe Creative cloud this morning and now Lightroom tries to open and crashes immediately.

By @Graham22938400khn3

Do you mean the Creative Cloud Desktop app? It is only needed if you have a subscription.

Are you getting any error messages?

Do you mean the perpetual license of Lightroom 6 or do you use Lightroom 6 from a subscription?

Please post the detailed error message word-by-word.

If you're using the perpetual license try the folloeing steps:

Try resetting the preferences of Lightroom Classic:  How to reset Lightroom Classic preferences (adobe.com)

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

Another possible reason for crashing can be a faulty catalog. 

Hold the Ctrl-Key while starting LrC. This opens a catalog selection dialog.  

First select the appropriate recent catalog and let it check it – note the checkmark "Test integrity of this catalog" to check its integrity. If that doesn't help, try to create a new one and see if this catalog works. If yes, you could then try to import your current catalog into the new one.