Can I use the same set of service accounts for 2013/2015/2016/365? I have 2013, 2015, 2016 systems working. Then on my machine used for 365 server, I installed 2016 and it worked. After I installed KB3205084(Dec 2016 update) I got an "invalid user" error when I click on "admission-System Settings" in CRM. After I got this error, When I when back to 2015 CRM wont even come up. It says permission problem. I also got a "query builder error" in 2016 when click on "system settings". 2015/2016 was working before this and I didn't change them. Could it be that the service accounts were damaged?
Thanks
Holly Li