Garmin 405cx won't sync workouts

I dusted off my Garmin forerunner 405cx to loan to a friend.  I wanted to put some interval workouts on the training calendar and sync it all to the watch.  I kept getting a sync error.  I believe it's because the workout had more than 40 repeats.  When I edited the workout to bring it down to a warm up, 40 repeats, and cool down it synced over just fine.