Is logging out and back in again a good way to deal with problems? Although it can be, it might not do what you think it does any more.
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You press the Power button, but don’t see the normal login window. How to interpret your Mac’s different screens, and what to do about them.
Universal App version of a utility to scrutinise your keychains and help diagnose their problems.
What do you do if your Mac starts up in the wrong language, or even worse if it’s stuck in the wrong keyboard when you’re trying to type in your password?
A detailed examination of what happens during the first few minutes after starting your Mac up. Vital for anyone trying to diagnose problems in that period.
The Eclectic Light Company 