Torben.Busk
Level 1
(0 points)
Q: I keep getting 'Unknown Error occurred 21' while trying to restore
It started with the apple logo just flashing on and off. So I went to reset my daughters iPhone by pressing the on/off button and the menu button simultaneously until the iTunes logo and the USB cable was shown on the screen. At that point, iTunes wrote;
'iTunes has detected an iPhone in recovery mode. You must restore this iPhone before it can be used with iTunes.
I clicked 'OK' and then 'Restore'. ITunes then went on by 'extracting software...' for a minute or two and then 'Preparing iPhone for restore...' The apple logo was then shown on the iPhone and a message box i iTunes;
'The iPhone 'iPhone' could not be restored. An unknown error occurred (21)'
The message box leads to 'More Information' that says that the error 21 ' typically occur when security software interferes with the restore and update process'
That's it. I have tried everything. (I think);
Checking for iTunes updates
Checking for OS (Win7) updates
Restarting the computer
Changed the USB cable
Changed the computer
Ensuring that I have administrator privileges and that iTunes has it as well.
Disabling the antivirus
Disabling the firewall
If you have any advice, please let me know.
Regards
Torben Busk
iPhone 4, Windows 7
Torben.Busk
Level 1
(0 points)
Thanks for helping out, but I already tried these steps.
I even tried this on a iMac with similar results. The only difference was that the errorcode was called 2001 instead of 21.
Today I took the phone to www.iphoneambulancen.dk. A guy (in Aarhus, Denmark) that specializes in iPhone repairs. I figured, that given his occupation he'd seen most errorcdes. Two hours later, he called me back, and told me that he had replaced the battery.
So, it turns out that a broken battery can cause this behaviour.
But thanks again
