During and initial sync of ~5200 records from an 'images' table we received this error:

Oct 22, 2016 11:39:39 AM com.prosc.mirror.config.server.SyncServer$3 call
SEVERE: Sync between filemaker8.oda.state.or.us / BeFoodSafe5 (FileMaker Server) and kwiddicombe macOS Desktop BeFoodSafe( username 'developer', running ProAdvanced 15.0.2 on 10.0.1.199, ping time: 215 ms, machine name: 'Developer' )
Last sync failed: com.prosc.sync.AbortException: Failure while recording changes from FileMaker Server filemaker8.oda.state.or.us/SyncImages: 0

Ultimately we removed all records in the Images table and added them back to the spoke table 1000 at a time and were able to get them sync'd to the hub table.

We also routinely received this error but were able to sync again and complete the sync:

Oct 22, 2016 5:57:08 PM com.prosc.mirror.config.server.SyncServer$3 call
SEVERE: Sync between filemaker8.oda.state.or.us / BeFoodSafe5 (FileMaker Server) and MSD macOS Desktop BeFoodSafe( username 'developer', running ProAdvanced 15.0.2 on 10.0.1.199, ping time: 65 ms, machine name: 'Developer' )
Last sync failed: com.prosc.sync.AbortException: java.lang.NullPointerException

we updated from 3.1007 to 3.11 today, and uninstalled and reinstalled MirrorSync as well to no avail.

Hey Mark, I've sent you a new build via our issue tracking system.

Thanks Jesse! Seems to have done the trick.

Mark