Hello there,
greetings from Germany.
I found a Solutions that worked for me and my friends(different plattforms Win 7 to 10 and 8 so 8.1 Mac.....)
We just changed the log from info to debug 1 on server and on the client(`s).
[Also try to disable SSL Encryption]
We reload the config on both an it worked just fine.
By Drag and Drop as well ass strg-c / -v.
I were able to change the log output to back to info and it still works.
For me this is a strange error, because effectivly i did nothing by it seems that something in the backend happend.....
Hope that this will Help.