If you are installing a ISV solution into a Contoso environment, and you suddenly see that you cannot synchronize, and you cannot see why:
Here is a tip that works for me;
Disable the track changes in the specified tables;
Then the synchronization is able to perform. After synchronization you can enable it again.
If you want to switch on/off in SQL, then this is the script for Switching off;
To switch them on again;
Happy Daxing !