Asus Zenfone 2 devices (ZE551ML & ZE550ML) can be manually updated to Marshmallow. But not everybody is happy with the new changes and performance of the Marshmallow builds. There are sudden freezes and slow touch response at times. If you too are not happy with the Marshmallow update and wish to downgrade to the old Lollipop, this post is for you. Read on to find the step-by-step guide on downgrading Zenfone 2 to Lollipop.
While the process is pretty straightforward, please do note that downgrading will delete all user data. So, backing up all important data is your responsibility.
Contents
Downgrading Asus Zenfone 2 to Lollipop (ZE551ML & ZE550ML)
This tutorial is written only for the ZE551ML & ZE550ML variants of the Zenfone 2. The process will be mostly the same for other Zenfone 2 variants, but please stay cautious and make sure you do not flash the wrong firmware on your device. Flashing the wrong firmware can damage your smartphone.
Part 1 – Download Zenfone 2 Downgrade Firmware
Asus provides official packages for downgrading from Marshmallow to Lollipop. Download the full package suiting your Zenfone 2 variant and proceed to the next part.
The above links are for WW firmware only. If you have a regional variant of Zenfone 2 (CN, JP; etc), please download files specific to your variant from the Asus website.
Part 2 – Install ADB & Drivers on PC
We will use ADB to push the downgrade file to the device. So, if you do not already have ADB and drivers already installed on your system, please download from the link below and install it.
Part 3 – Sideload Using ADB
The final step is to boot the phone into recovery mode and then flash the downgrade package using ADB.
- Power off the phone.
- Press and hold Volume Up & Power keys together. The phone will boot in fastboot mode.
- Use the Volume keys to select Recovery Mode and press Power key to select.
If you see a dead android icon, press and hold the power key. Then quickly press volume up key. - Choose Apply update via ADB.
- Connet your phone to the PC.
- On your PC, browse to the folder where you have saved the downgrade package file. Once here, right-click while holding the shift key and choose Open command window here.
- Pass the following command in the command prompt window. Replace file.zip with the name of the downgrade package.
adb sideload file.zip
The command will start serving the downgrade package to your phone. Reboot your phone after the command finishes. Your phone will be back into the Lollipop version 🙂
hello what if i have TWRP?
Hi i want to downgrade my zenfone 2 but we dont have PC , is there any other way to downgrade it withoust using PC ? Please how. TIA.
Hi, you should be able to use Sideload from SD card to complete the downgrade. Just put the downgrade package into your SD card and use recovery to flash it.
Flawless, no complaints
Hi there
Is this downgrade will effect to security patch level also?
Yes, the entire system will be downgraded.
After this can I upgrade to Marshmallow in asus zenfone ze550ml if can please tell me how I’m desperate to know about it
Yes you can update to Marshmallow again by downloading the Marshmallow ROM. You can follow this guide.
Hii ,
I tried to update with sd card option , but after checking firmware integrity it shows status 7 stating cannot upgrade with an older version
You need to download the specific downgrade package. Simply downloading an older firmware will not work 🙂
I have downloaded UL-Z00A-WW-2.20.40.198-user.zip from asus website for my ZE551ML. I tried both downgrading via adb sideload and with sd card. Both case goes through checking integrity phase then showing cannot upgrade to a lower version , Status 7 code
Is it necessary to do a factory reset before the process
i couldnt downgrade..
never build problem.
Are you flashing the actual downgrade package? A package marked on the Asus website as Downgrade?
Thank you very much Narender Singh.
I used SD Card instead of ADB. It worked fine.
your phone is rooted???
It doesn’t require a rooted phone to install the stock ROM.
Please tell what exactly to write in the command prompt window while updating via ADB for asus zenfone 2 ze 550ml
You just need to write ADB sideload followed by the full name of the ROM file.
Thanks narender ji
while updating phone to M phone switched off now my phone is not starting not showing any sign
so how to downgrade phone now?
Can you check if you’re able to enter recovery mode or not?
first upgrade then downgrade..?? Bhai pagal blog hai tera…….
Toh mat padh. Kisne dhakka kia hai tere sath bhai?