FreeFileSync Forum

I have been used FreeFileSync on PC since many years without trouble.
I switched to a modern MacPro ( OSx El Capitan )
I am trying to sync a 32G USB 3.0 key ( formatted on Mac : FAT 32 / MBR )
The Compare process is ok.
The Sync process ( mirror mode ) frozes after a few seconds.

I tried three keys ...