i think i erased everything and now when i try to start up my mac i get a no entry sign on a black screen. ive tried letting it do what it was doing when ghere was a spinning globe and i tried downoading the os but neither did any good
h.
Question marked as
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When you see a circle with a slash symbol instead of the Apple logo, it means your Mac couldn't find a valid System Folder to start up from.
If you're using your Mac at a school or business, it might be trying to start from the wrong version of macOS. Contact your IT department for more help.
If this is your personal Mac, try reinstalling macOS using macOS recovery.
About the screens you see when your Mac starts up - Apple Support