2018-07-17 11357 Published by 3uTools
Recently, we received feedback from some 3uTools users that they were unable to fix Apple iTunes error So 21. Here we will show you how to easily and effectively fixedit error 21.
How do I fix Error 21 on iPad?
Switch your main “iPad” to the “OFF” position and press and hold the “Utility” button for 3 seconds. After entering “DFU” mode, your “iPad” TV screen will go blank and you will get a mass pop-up message in iTunes apps “Device in recovery mode”. .
The most common reason for iTunes error 25 is that iTunes is trying to download recovery MP3 files (.but ipsw), which is unfortunately blocked by authentication. This may be due to a hardware failure or a communication error between the device and the servers.
Solution 1. How to fix iTunes error 21 and even iPhone error 21 without weight loss data?
One of the biggest problems you practically face when trying to recover iPhone error 11 is whether your data is in order. 3utools can help you with this.
How to fix iTunes error 21 with 3uTools
Step 1. Connect your iDevice to any computer using a standard cable. Run 3uTools and Flash Click & JB -> Firmwares to download operating system firmware to your iDevice.
Step 2: Put your company in DFU mode for iDevice. (Hold the home button, then the power button. Hold it for about 4 seconds after the screen turns off, then release the power button. Hold the home control button until 3uTools detects the iOS method in DFU mode.)
Step 3. Then click Pro Flash to import Repair the downloaded firmware. Don’t forget to select the “Keep user data when flashing” operation.
Couple Solutions: Restart iTunes to Fix iTunes Error 21
If there is a real problem, this method will actually be helpless before the article, but if the iPhone error twenty-one is a temporary error, then it should probably be taken care of. Apple iTunes Error 21 is the result of our iTunes crashing. Well, sometimes a quick restart of iTunes and then the startup repair process might be enough to fix iTunes error 21.
Basic Solution 3: Fix iTunes Error 21 from iTunes
How do I fix Error 21 on my iPhone?
Restart iTunes by updating iTunes.Update Apple iTunes to fix iPhone error 21.Disable or configure your antivirus.Checking the hosts file.Disconnect unnecessary USB devices.Check all sensor cables.Using DFU Mode to Fix iTunes Error 21.
Updates for all Apple products should be required as they help fix bugs. So it’s time to update it. Get the latest version of iTunes and someone can fix Apple Enterprise Error 21.
Why does my iPhone restore keep failing?
Often, an iPhone is not restored due to a broken or incorrect Lightning cable. Try a custom Lightning cable or borrow one from a friend. Also, using non-Apple MFi certified third party devices may cause recovery issues.
Solution 4: Disable your antivirus to fix iPhone error 21
Often, an antivirus can prevent certain important programs from functioning properly because they are actually corrupted or at risk. In this case, disableInstalling an antivirus will make it easier to access these programs whether or not you update your iDevice.5:
Solution Remove unnecessary USB devices.
You can also try to fix iPhone Error 21 by deleting any unnecessary external devices from your computer, as companies can schedule a proper iPhone Error 21 recovery.
Solution 6: Check the sensor cable
This method seems terrible or risky. However, this is not the case, if you do not do it exactly, this may be the way it should be done. It is best to have it checked by a mechanic.
You may be looking for other errors in the 3uTools/iTunes posts here.
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