Could you please help us with the following details:
- Are you working on a Mac or Windows computer?
- Why are you trying to reset the preferences?
- May I also know the Lightroom version you are using?
I read another post about resetting preferences to possibly fix issues, so I tried it. I thought maybe something had gone wrong somewhere.
This is probabaly caused by the graphics processor, which normally can be disabled in preferences.
But since you can't access preferences, follow this procedure:
Close Lightroom. With Windows Explorer, navigate to C:\Users\[your username]\AppData\Roaming\Adobe\Lightroom\Preferences
Open the file Lightroom 6 Preferences.agprefs in a text editor, like Notepad.
Cose to the end of the file there is a line that says useAutoBahn = true, - change this to useAutoBahn = false,
Save and close the file. Now try to start Lightroom.
When I open that file, mine doesn't look like that. It is very short. Only a couple of lines. But it does have a line that says 'recentlibraries20_missing'. I imagine that this may be an issue as well, yes?
If this doesn't fix the issue, delete the prefrerences file - it could be corrupted.
Lightroom will create a new preferences file when you launch it.