How to flush out sync settings in X7 and start clean

Does anyone know the command to use with X7 to flush out sync settings and start new (on the user end, keeping the synced library on the web intact)?

I once got this from tech support but can’t find where I recorded it; and I am unable to sync one of my machines with the other at the moment (it stalls). I’d like to get it to “forget” what it knows and redownload the library. tx