tll_01 Said:
"Mac bugging out when I enter my Apple ID: I was working on my Mac when the window popped up to login to the iTunes Store which I don’t remember clicking on. When I enter my Apple ID the window disappears then pops back up all over my screen repeatedly."
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Logging Back In:
Boot in Safe Mode:
In Safe Mode, Login Items do not run at login, certain preferences are set aside, and damaged system files are then reset. So, once booted in to Safe Mode, wait 30 seconds, and then boot up normally, attempting another login. For instructions, go here: How to Use Safe Mode on your Mac - Apple Support