I have a question, I just started using Collector for ArcGIS recently and I downloaded my data to be offline on my iPad since I would not be WIFI. Now when I go to sync back to my ArcGIS online account I get the error message in the attachment. I am not sure how to fix this or what is causing this to happen. Any suggestions on how to get my data back into the online environment?
I don't think so since it's now 2017 and I encountered this problem today. This has been a problem since 2014 and there's hardly any any Esri support for this. The best solution I've found is trying to sync by putting the data onto itunes (or similar program) and then trying from there. I will post if this works for me. This is a headache.
By using a much better internet connection I solved the upload problem for me. My error message was "sync error illegal start of token." I would suggest using a home network; not a public, school or work wifi connection or even trying it at times of the day when internet traffic is low.
