Huawei Mobile Phone Update EMUI System FAQ

1 What are the advantages of updating EMUI on my phone?
(1) Updating will provide you with the latest OS version for optimum performance.
(2) Updating provides additional functionality.

2 Are there any risks involved?
There should be no risks involved. Updating the OS optimizes performance and helps to fix some system bugs. Nevertheless, you may experience some minor hiccups when updating. As the update file may be quite large, you should download the file over a stable Internet connection. You should also be aware of incurring mobile data charges and ensure that you have enough storage space.

3 How can I update EMUI?
You can update EMUI online or via a microSD card.

4 How long does it take to update EMUI?
Excluding preparation time, updating using a microSD card takes no longer than 10 minutes. The time required for an online update depends on the speed of the Internet connection.

5 What precautions should I take before updating EMUI?
(1) Ensure that you back up all the data on your phone (such as contacts and messages).
(2) Prepare a microSD card that has at least 2 GB of free space. You don't need to format the microSD card.
(3) Charge your phone battery to at least 50% in order to ensure that your phone has enough battery power to complete the update.
(4) If you update online, you are advised to connect to a Wi-Fi network to avoid incurring excessive mobile data charges when downloading large files.
(5) When updating using a microSD card, ensure that the microSD card is accessible and that it has sufficient storage space.

6 My update failed. Why?
(1) Your phone had insufficient battery power.
(2) You downloaded the wrong update file.
(3) Your phone had insufficient storage space.
(4) The microSD card was damaged or of poor quality and data access was interrupted.
(5) The Internet connection was unstable, so the update file could not be downloaded.
Source: http://www.gizok.com/blog/huawei-mobile-phone-update-emui-system-faq/