Synchronize folder then LR hangs up

[DClark064]

When I try to synchronize a folder that has some image files added, LR searches for new files and find some, then when I click the Synchronize button loads the "From - To" window with no thumbnails showing, and then just hangs there.  If I check the Task Manager, LR is using about 12% of CPU.  It will stay that way indefinitely.

I have optimized the database, restarted, rebooted, removed and reinstalled LR.  Nothing seems to help.  I can import files with no difficulty. 

Anybody else seeing this problem?  Any way to fix it?

[Alfredo Art Studio]

While folder synchronization is not working, I am able to import the files from the same folder.

1. Go to import and select the folder where you have the pictures (this will be a mix of imported and new pictures)

2. Lightroom will only select the new one

3. Import as usual