Server 10.3.1, SDE gdb has archiving and editor tracking enabled.
Secured feature service using built-in token store; server is not federated.
Feat. service added to AGOL, with service credentials stored with item.
Several successful sync's have been preformed, then Collector started reporting "illegal start of token" errors.
I think there are three possible reasons I am aware of:
I am thinking if it may be related to reason #1.
I checked with field staff and new photos were always captured, never added from library, so we can rule out #1.
Since several prior sync's worked, I'm guessing it's either #2 or #3.
What is a good value for uploadReadAheadSize ? It's currently the default value 49152 byes. MS docs say 0 - 2147483647 bytes are acceptable values.