[Huawei P20 Guides, News, & Discussion] smohanv:
I bricked my phone after flahing EMUI 9.0 and subsequently First Ever ROM build 10/12/2018 as well. My phone was booting in to stock eRecovery only. Ofcourse I was able to boot in to bootloader / fastboot mode. I booked appointment with Huawei recommended service centre. I wanted to give one last try and finally gave life to my phone. Here is the steps that took through.

Note: These steps works for downgrading to EMUI 8.1 as well

For downgrading, skip all the steps and go to step 10 after flashing custom recovery explained in Step 7

Getting the device ready:

1. Download EMUI 9.0 from here https://pro-teammt.ru/firmware-database/?firmware_model=CLT-L29C432&firmware_page=0//

2. Unzip the file UPDATE.APP from Update.zip

3. Using EMUI extraction tool extract following image files (see step 4 below) from UPDATE.APP. Download tool from here https://www.androidfilehost.com/?fid=11410963190603873616

4. Extract, CUST.img, KERNEL.img, RECOVERY_RAMDIS.img and System.img and copy these files in the same folder where you have ADB tools. Download ADB tools from here: https://www.androidfilehost.com/?fid=11410963190603873622 Unzip files. You will find a file cmd-here.exe. Run this file to get to open command prompt in your PC to the same folder where you have this ADB tools extracted.

5. Put your phone in to Fastboot mode (Switch off your phone, Press and hold volumn down button and connect USB with PC)

6. Flash the image files in the same order with fastboot commands as below,

fastboot flash cust cust.img

fastboot flash kernel kernel.img

fastboot flash recovery_ramdisk RECOVERY_RAMDIS.img

fastboot flash system system.img

7. Now flash custom recovery. Download custom recovery from here https://www.androidfilehost.com/?fid=11410963190603866808

Fastboot flash recovery_ramdisk twrp-3.2.1-0-charlotte-mod.img

8. Now restart your device with command below,

fastboot reboot

As soon issued this command, pull out of USB cable and keep holding volume up button until HUAWEI logo comes up disappear. It will now boot in to TWRP recovery.

9. Check file names in TWRP (Advanced > File Manager) are readable under folder sdcard. If file names are appearing as a junk, it means that you need to decrypt your data partition. Follow the steps below,

>> Wipe > Format data

>> Hit home button and Reboot > Recovery

>> Download and copy RemoveEncryption-P20Pro.zip file in to sdcard folder (Internal storage). This file can be downloaded from here https://www.androidfilehost.com/?fid=11410963190603866806

>> Flash RemoveEncryption-P20Pro.zip

>> Hit home button and Reboot > Recovery

>> Wipe > Format data

>> Hit home button and Reboot > Recovery

NOW YOU ARE READY TO FLASH OFFICIAL EMUI 8.1 OR 9.0 (as you like). You have no root exploit available for 9.0 at the moment and also Google Pay will see the device as rooted because of unlocked bootloader.

10. Follow the steps below,

## Download the EMUI version that you need from the link https://pro-teammt.ru/firmware-database/?firmware_model=CLT-L29C432&firmware_page=0/

## Rename the file update_full_CLT-L29_hw_eu.zip in to update_all_hw.zip

## Create a folder ZIPS-HERE in the same folder where you have ADB tools (as explained in the section above) and put both update.zip and update_all_hw.zip in this ZIP-HERE folder.

## Download update_data_public.zip for EMUI 8.1 from this LINK and copy to the same ZIPS-HERE folder. You do not require update_data_public.zip for EMUI 9.0

## Download this nocheck.img file and copy it in to the same folder ZIPS-HERE. link here: https://www.androidfilehost.com/?fid=11410963190603873636

## Issue following commands (you can copy and paste in the command window)

adb shell twrp decrypt

adb push ZIPS-HERE/update.zip /data/update/HWOTA/update.zip

adb push ZIPS-HERE/update_all_hw.zip /data/update/HWOTA/update_all_hw.zip

adb push ZIPS-HERE/update_data_public.zip /data/update/HWOTA/update_data_public.zip (this command line is not required for EMUI 8.1)

adb push ZIPS-HERE/nocheck.img /data/update/nocheck.img

adb shell "echo --update_package=/data/update/HWOTA/update.zip > /cache/recovery/command"

adb shell "echo --update_package=/data/update/HWOTA/update_all_hw.zip >> /cache/recovery/command"

adb shell "echo --update_package=/data/update/HWOTA/update_data_public.zip >> /cache/recovery/command"

adb shell dd if=/data/update/nocheck.img of=/dev/block/bootdevice/by-name/recovery_ramdisk

adb reboot recovery

WAIT AND WATCH THE FLASHING HAPPENING VIA HUAWEI eRecovery. Once done, restart your phone. Your phone is back to life.

So far I have soft bricked several times in the past few days and brought back to life. As long as Bootloader (fastboot) partition is not disturbed, we are good to recover our device.

..