I am running ArcGIS for Server 10.5 and Portal for ArcGIS 10.5, as well as Collector 10.4.2 on my iPad.
I have all of my features configured for archiving and with Global IDs.
I was using the Sync feature last summer, on 10.3, but after updating to 10.5 I get errors, and it won't let me Sync my changes back on to the Server.
Here is the error that I keep getting, which I don't understand. I am not using any versioning, so it shouldn't be dealing with replicas at all.
I'm not sure if anything has changed, since it was working without any errors on 10.3