Every iPhone user faced with some issues with the device. There are certain errors that may appear with no apparent reasons, which is why you won’t be able to use your phone normally. The good news is – most of the issues you see, you will be able to fix with some simple solutions. For this time, we have prepared 5 ways to fix iPhone error 21 that usually appears in the restoring or updating process. So let’s begin with potential solutions.
You may want to check out:5 Ways To Fix IPhone Error 2001
5 ways to fix iPhone error 21
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Source: itv.com
Solution No.1: Restart iTunes
Sometimes, the glitch will be fixed if you restart the program. Simply turn it off, and turn it on again. Connect your device to your computer, and try to restore or update again.
Solution No.2: Update iTunes
Whenever you want to perform the restore or update, make sure that you have the latest version of iTunes installed on your computer.
Mac users:
- Open the program.
- Open the menu, and click on iTunes.
- Select check for updates.
Windows users:
- Open iTunes.
- Open the menu bar and select Help.
- Click on Check for updates.
Solution No.3: Turn off your anti-virus
In many cases, for some reason, the anti-virus program you installed on your computer may cause different errors, included the error 21. Turn it off, and try to update your device again.
Solution No.4: Remove unnecessary USB devices
Make sure to unplug all the devices you don’t need at the moment from your computer. Maybe some of those devices are causing the problem.
Solution No.5: Sensor cable
This step seems complicated, but it’s not. Simply open your device, and remove the screw used to connect the battery. When you see a sensor cable, simply unplug it, and put it back.
These are the simplest 5 ways to fix iPhone error 21 you can try on your own. You cannot cause any damage. If the error is still there, we advise you to contact Apple.