@amadeusp81 - Did you experience this?
So, I have installed (upgraded) to Sierra, but something weird is happening. EVERY time I startup, I'm forced to go through the startup process after logging in: you know, the iCloud login, then the "setting up your Mac" thing, even the "optimizing your mac" process....no matter if I skip everything, or login properly to iCloud, etc the process repeats at every boot.
Quite literally, this happens every time I startup, I have to go through this process (when it should happen only once).
Any ideas out there? Once I'm logged in, and have gone through the process, things seem fine. But it's a bit tiresome to go through this over and over again and again.
This is on a second Hack: GA-Z170X-UD5 TH, 32 GB of RAM, GTX 980 card, Sierra 10.12.2