When I try to open Lightroom 6, it gets stuck on the splash screen.
If I click on the application icon, it shows 'application not responding' and the only option is to force quit.
If I leave it, it closes itself after a few minutes.
It was working fine before, and I haven't run any updates - although I did empty the trash just before trying to open it.
Lightroom 5 is working fine.
I'm on Mac OSX.
Please use the below link to update Lightroom 6 to 6.1.1
Once Updated, try Lightroom.
Refer the Article: Lightroom CC 2015.1.1/Lightroom 6.1.1 Update
Let us know if it helps.
Thank you so much, that's done the trick!