Error 21 trying to update. HELP!!!

Question

Error 21 trying to update. HELP!!!

So, i have an iPhone 4 and i just tried to update to iOS 5, but i keep getting an Error 21 saying it cant be restored.

I did a little research and people seem to say to put it in DFU mode (holding the power/home, then releasing the power), but that doesnt work.

I updated iTunes thinking that might resolve it, but it didnt.

I tried my other USB port also, to no avail.

Can anyone out there help me out??

Not that it needs to be said, but ill mention it is NOT jailbroken.

Thanks for any help!!!

-Sin

MacBook Pro, Mac OS X (10.6.8)

Posted on Feb 4, 2012 1:49 PM

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Answer 1

Feb 4, 2012 8:09 PM in response to AbominusRules

DFU mode is correct.

Check your hosts file in HDD/etc/hosts.plist (this is a hidden file, so enable hidden files and folders)

Make sure the following is NOT in your hosts property list: #74.208.10.249.gs.apple.com

* You may need to change your permissions to save your hosts file.

If that line is present, server communication in iTunes fails, causing 21 in DFU and 1600 in Recovery or normal mode.

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Answer 2

Apr 19, 2012 7:49 PM in response to xtremecarbon

Could someone please elaborate on the above post? I've tried DFU mode, and am not sure where to be looking for these hosts... I googled a few terms and phrases, but it's not helping.

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