UPD.
It worked when I pressed and held Alt along with the power button.
Same problem :( Help
I did the following (by TheRobotMaster ):
Power down the mac. 2.hold the Option-Command-R and power button. 3.a world logo will show and start loading.
Then I saw an error and folder icon with question mark started blinking. Nothing worked since then, just the icon blinking :(
tequilacat
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