I cannot sign in to Apple services/apps on device (iTunes, Cloud account, etc.)
I can sign in to appleid.apple.com but not into any services on my Mac, as iTunes, Cloud etc.
After several trials I get a suggestion to press the "Forget Password?" button:
iCloud:
iTunes:
Appstore:
I use my Apple ID on this computer for years, with no interruptions.
A few months ago I signed in also from my Mac laptop I got from work, and I can sign in from it.
I think the problem started after a recent OS update, though I'm not sure.
Though this post is under Mac OS X El Capitan, I use macOS Sierra, latest update.
I tried replacing Apple ID password.
I tried tried restart/shutdown.
Mac mini, macOS Sierra (10.12.5), null
