frozen screen while upgrading

Hello,

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If your iPhone, iPad, or iPod touch won‘t turn on or is frozen

Also see:

Updating iOS: common issues and solutions

Good luck.

IMac frozen upon trying to upgrade Os . This is second time it happened. Apple says it’s ‘ a GLITCH “ . It’s not merely a glitch when it happens each upgrade. It’s a royal pain in the…..

last time they had to delete all files and reinstall OS. IMac down for 3 days .

any solution?