Q: during restart at itune Iphone 4s hanged

Hi Raj!

I understand you're getting error 29 after updating the iOS software on an iPhone 4S.  I'm happy to help with this, because I know it's important to have your phone working right.  Please try all of the steps in the first link listed below.  If you're still having issues, you'll see specific instructions for error 29 under "Check for hardware issues" in the second link.

If you see an error when you update or restore your iPhone, iPad, or iPod

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