Apart from Error 3194 there is another common problem called Error 21 when you are trying to restore or upgrade your iPhone or iPad. Error 21 gives you a message stating that “Device could not be restored an unknown error has occurred“. Many people requested that they are getting this message whenever they want to update their iOS to 6.0.1. Today I am going to show you how to solve this simple problem. Error 21 occurs because Apple changed the method of updating iOS Firmware with the release of their 5th version. Nowadays they verify if you are using a non-jailbroken device before updating or restoration. Follow the steps carefully to fix it.
Steps for Fixing Error 21
1. First, you need to download the specific IPSW for iOS 6.0.1 on your device. If you are planning to restore your iPad or iPhone then you can search for the specific version IPSW in Google and I am sure you will find the download links.
2. After downloading the entire package connect your device to the computer/mac. Hold the home and power button for 10 seconds. The device will shut down. Keep pressing the home button until you see an image of a dock connector. This method is called Entering DFU Mode which is critical for all software update operations.
3. Switch off your internet connection
4. When you are inside the device update page Press Shift and then click the restore button. This will pop up the window where you can select your IPSW and install iOS 6.0.1 or restore your device. In this way you will bypass Error 21 check from Apple.
If you are still facing any problem then please comment them below so that I may provide you with more tips the fix the issue.