Register FAQ / Rules Forum Spy Search Today's Posts Mark Forums Read
Go Back   MacRumors Forums > iPhone, iPod and iPad > iPhone > iPhone Tips, Help and Troubleshooting

Thread Tools Search this Thread Display Modes
Old Jul 24, 2010, 02:44 PM   #1
macrumors newbie
Join Date: Mar 2010
Help, Cant restore iphone 3GS, unknown error 21

When attempting to synch my Iphone 3GS i was prompted to update the OS to 4.0.1. During the installation an error message appeared, unknown error 21 was given as the reason. After this the iphone has apparently entered 'recovery mode' and needs to be restored before it can be used again. However when i try to restore it it gives the unknown error 21 and doesnt complete the task. I was initially using ITunes 9.2.1 and have tried to restore on a different computer with another version of itunes but get the same error message. Looking up error 21 apple seems to suggest this is an error that occurs with anti virus software interfering but i am not running any anti virus software that i am aware of.

Can anyone help or have i bricked my iphone?
Steve0407 is offline   0 Reply With Quote
Old Aug 3, 2010, 05:39 PM   #2
macrumors newbie
Join Date: Aug 2010

Hi, Using a PC you need to produce a new account with admin settings. Then run Itunes and as you are a new user it reconfigures Itunes. Plug in your iphone and restore as normal.

I then went back to my normal account and restored from backup.

Works a treat!
davidlanglands is offline   0 Reply With Quote

MacRumors Forums > iPhone, iPod and iPad > iPhone > iPhone Tips, Help and Troubleshooting

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
thread Thread Starter Forum Replies Last Post
Why cant I put music on my iphone 3gs (error 13019)? kyle116 iPhone 1 Nov 3, 2011 07:57 PM
iPhone unknown error (-200) horace528 Mac Applications and Mac App Store 0 Oct 10, 2011 10:14 AM
iPhone 3GS Major Problem =/ marc.richards7 iPhone Tips, Help and Troubleshooting 1 Mar 10, 2011 10:09 AM
iphone 3gs jailbrake help iphone3gs.ash Jailbreaks and iOS Hacks 3 Nov 11, 2010 10:05 AM
Can't restore iPhone getting unknown error 1015 steelersfantn iPhone Tips, Help and Troubleshooting 1 Jun 14, 2010 09:16 PM

All times are GMT -5. The time now is 05:37 PM.

Mac Rumors | Mac | iPhone | iPhone Game Reviews | iPhone Apps

Mobile Version | Fixed | Fluid | Fluid HD
Copyright 2002-2013,, LLC