“Do not enter sign”
My Mac book has a “do not enter” sign with a black background when turning on and won’t let me get any further into it. What’s going on and how do I fix it?
MacBook Pro 15″, macOS 10.13
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A circle with a line through it means that your startup disk contains a Mac operating system, but it's not a macOS that your Mac can use.
Follow instructions and guidelines from this article by Apple ➔ If your Mac starts up in a circle with a line through it - Apple Support.
Axel F.