QUOTE(coldfission @ Dec 30 2016, 09:07 PM)
I'm using b321 now without root and unlocked bootloader.
1. The 2 zip files only can be install via twrp. Means you need to unlocked your bootloader and install twrp(warranty will be void).
2. Another method is to downgrade your firmware to L29C636B211 via dload and hope you will get B521 OTA update. This method is without unlocked bootloader and twrp.
Method no. 2
** Make sure you backup your files before proceed.
1. Download L29C636B211 "update.zip" firmware.
2. Extract update.zip and copy update.app to dload folder at your sdcard/usb otg. If dload folder doesn't exist. Create the folder.
3. Shutdown your phone
4. Insert/plugin sdcard/usb otg
5. Press and hold volume up + down + power
6. Release it once huawei logo appear.
7. Wait until complete and let it load. ***
8. Once you're in. Go to Setting -> Software update.
9. You will get B521 OTA update. (I assumed you have registered as beta tester.)
*** If is doesn't load. You need to wipe the cache by entering erecovery. Press and hold volume up + power. Release it once you see huawei logo.
If you don't mind to void your phone warranty then only I will guide you using the method no. 1
Good luck.
This post has been edited by dexz: Dec 30 2016, 09:42 PM