The linked article will both show you how to reset your Mac’s password if you’ve forgotten it and, at the same time, demonstrate how easy it is for someone else to do this to your Mac if they get their hands on it.
As pointed out by reader Marek Bell, this technique will not work if you have File Vault enabled, which you should.
Better reading is Apple’s official support page that walks you through more traditional approaches to solving this problem.
This will not work if you have FileVault enabled, which is definitely you should have on.
There’s steps there for recovering if FileVault is on, too, even without the recovery key.
(I haven’t walked through them and I suspect you still need at least one password to the machine OR the recovery key.)
They changed the link after my original comment. Yeah, the Apple page is much better. Thanks for mentioning me Dave 🙂
My apologies, I didn’t see that happen. 🙂
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