How do I fix Error 21 on iPhone 4s?

How do I fix Error 21 on iPhone 4s?

Here are the steps to fix the iPhone error 21.

1. Restart iTunes by updating iTunes.
2. Update iTunes to Repair iPhone Error 21.
3. Turning Off or Adjusting Your Anti-Virus.
4. Checking the Host File.
5. Unplugging Any Unnecessary USB Devices.
6. Checking the Sensor Cable.
7. Using DFU Mode to Fix iTunes Error 21.

Why does my iPhone restore keep failing?

Oftentimes, an iPhone won’t restore because a broken or otherwise faulty Lightning cable. Try using a different Lightning cable, or borrow one from a friend. Additionally, using third-party cables that are not MFi-certified by Apple can cause restore problems.

How do I fix my iPhone 4 stuck in recovery mode?

Press and hold the Power button with the Home button. Keep holding both buttons for 8 seconds, then release the Power button but keep holding the Home button. Your iPhone is in DFU mode if it appears on your computer but the iPhone screen remains blank. If anything is on the screen, return to step one.

How do I fix Error 21?

Dial *#*#4636#*#*. Refresh it then the problem should be resolved!

How do I fix error code 21?

Method 1 – Wait & Press F5: This method is one of the easiest ways to fix the error code 21 on your PC. You just wait for a few seconds and then, you need to press the F5 key. It will update the view of Device Manager and so the error will probably go away.

Why won’t my new iPhone restore from backup?

If your iOS or iPadOS device can’t restore from a backup because the backup is corrupt or incompatible, make sure that your computer is updated. If you still can’t restore the backup, you might not be able to use that backup. Try to use an alternate backup or an iCloud backup, or Contact Apple Support for more help.

How do I get my iPhone 4s out of recovery mode?

How to Get Out of iPhone Recovery Mode

1. Unplug the device from the USB cable.
2. Hold down the Sleep/Wake button (or Side, depending on your model) until the iPhone turns off, and then let it go.
3. Keep holding until the Apple logo reappears.
4. Let go of the button and the device will start up.

How do I fix Error 21 on Vodafone?

(The 21 error code actually comes from the operator’s network, and has nothing to do with Android as such.) Removing the extra 0 solved the problem. If above mentioned methods are not working, you may try installing 3rd party SMS applications (eg., EvolveSMS) instead of Google messenger. Hope it helps.

How do I fix my SMSC number?

To set or change the SMS service center number on your SIM card

1. From your Home screen, tap the Application screen icon.
2. Find and tap Phone.
3. If the dialpad does not appear, tap the dialpad icon.
4. Type *#*#4636#*#*.
5. Tap Phone information.
6. Scroll down to SMSC.
7. Tap Refresh to get the current number and the format it uses.