[ZenFone 2 Android Development] keepfishes:
Step by step rooting guide V2_15 firmware

So as promised here is the noobs guide as to how to ROOT the Zenfone 2. Firstly I'd like to thank everyone who chimed in in this thread, I got info from bits and pieces everywhere, but I'd like to specially thank the OP [MENTION=1813976]shakalaca[/MENTION] and also [MENTION=1167089]-fluffy-[/MENTION] for giving me extremely prompt replies and help and pointed me to the right files. I hope this guide makes it easier for all! Do let me know if there is any misinformation, I will be sure to take it out!

First things first: (get this straight, don't download the wrong firmware and flash the wrong thing...)

ZE550ML = Z008

ZE551ML = Z00A

Also I have the WW version of the phone, I don't know if this guide can work for the TW or CN versions, those who have tested and tried please let me know!

All the steps below were tested on Windows 8.1 64 bits, I do not know if they will work on other OS...

Here goes:

1) Current latest version (as of 7 May 2015) of stock ZenUI rooted version of Android 5.0 is here on the first post, and is version 2_15.40.XX (depending on Z008 or Z00A). Disconnect your phone from your PC.

2) Download the entire folder. It should be a total of a 1GB+ download. Take note of Z008 or Z00A!

3) Download the files attached in this post. These will be all the files we need.

4) Unzip the FlashTools.zip and adbsetup zip file into the folder named "FlashTools"

5) Install the adbsetup.exe file.

6) In the downloaded folder, unzip the contents of "Z008_WW_2.15.40.11_system_w_root.zip" (or the corresponding zip file for your model) using WinRAR into the same folder, it should automatically create a single "system.img" file of 2GB+ in size.

7) Once done, we just need 3 of the files. Copy these into the "FlashTools" folder:

1) boot.img (~ 11MB)

2) recovery.img (~ 11MB)

3) system.img (~ 2GB)

Everything should look like this:

8) Open command prompt as Administrator (right click, Run as administrator).

9) Navigate to the "FlashTools" folder via DOS commands. Would make life a lot easier if you just copy the Flashtools folder to the C:\ Drive. Just follow the commands in my screenshot! (ignore droidboot.img, it shouldn't be there)

10) Pick up your phone, power it off. Once it is off, hold down the volume up button and hold on to the power button until the phone vibrates. After the vibration stops, release the power button and continue pressing the volume up button until the green Android robot appears. You should see a blue line below saying "FASTBOOT CMD WAITING"

11) Connect your phone via USB to your computer.

12) Copy and paste the following commands in the command prompt window (line by line) and press enter after each line. WAIT for the process to complete before copying and pasting the next line:

fastboot flash recovery recovery.img

fastboot flash boot boot.img

fastboot flash system system.img

The last step will take quite a while before it returns to the blinking cursor. Once it does, it's done and you can plug out the USB and press the power button, reboot your phone and when it starts up, your phone is ROOTED! You should see a # sign in the status bar!

Now read the first few posts in this thread again to see what you should or should not do when using this rooted ROM! There is something about updating and causing a bootloop (which I haven't read I'm sorry) so please read properly before using!

Cheers!