Do you have tried to deactivate the GPU support?
Open Lightroom > Edit menu > Preferences > Perfomance tab > Uncheck GPU > Restart Lightroom.
I turned off the GPU and restated LR, the problem remains.
I select a import source, for about five seconds everything appears fine then the beach ball starts and I am forced to quit.
I know it will get figured out, but it is a bit frustrating as most of the reason I got a new computer is to work LR better. I was on a 2009 iMac.
Thanks for the support
seems a corrupted .plist is the issue
the issue came right back after deleting the .plist so I decided to give abode chat another chance. The next remote service surmised it was a corrupt catalog and of ext HDD problem.
We created a new catalog and imported from the old one and I used my clone backup and poof, everything works perfectly.
thanks the al lmighty for backups