There is a possibility that your i Phone or i Pad is out of storage so that the i OS 11 software update failed.Just delete some useless data and release more space for your new i OS version before downloading.When the error message “An error occurred downloading i OS 11” appears, just click on the Close button to exit the error message. After restarted, tap on “ Download and Install” again.
This method works well most of the time, but we suggest you to update your i Tunes to the latest version before start.To do so, you just need to plug in your i OS device to your PC or Mac and when i Tunes launches, click "Check for Update", which can be found under Summary pane.You may choose to update your device wirelessly (over-the-air) or download the update through i Tunes.The first method requires a stable connection to the Internet (through Wi-Fi) while the latter requires you to have a computer that has the latest version of i Tunes software installed.Updating process using both methods is easy and simple.
But even so, there are still some people who are having trouble getting an i OS update installed on their i OS device through either methods.
Connect device to computer and go to i Tunes Summary tab.
Hold down SHIFT key on Windows PC or Alt/Option key on Mac and click the “Restore i Phone” button.
Actually, this is not new, rather one among the common issues that appeared in the previous i OS version and affected a lot of i OS users globally.
The good news is, in this article, we will share you 7 possible solutions you can try to resolve Apple software update error occurred while installing i OS 11 update (also can be applied to i OS 10.3.3/10/9/8) on your i Phone 7/7 Plus/6s/6s Plus/6/6 Plus/5s.
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