Install /e/OS on a Xiaomi Mi MIX 2S - “polaris”

The instructions in this guide will assist you to install /e/OS on your polaris. Please read through the instructions at least once before actually following them, so as to avoid any problems later.

It is important that you know that downgrading Smartphones on OS versions greater than the /e/OS OS version you plan to install, can cause instability or at worst brick some devices. We recommend that you check your current OS version, before attempting the installation.

It is advisable to flash your device only if you know what you are doing and are ok taking the associated risk. All /e/OS builds are provided as best effort, without any guarantee. The /e/OS project and its project members deny any and all responsibility about the consequences of using /e/OS software and or /e/OS services.

Requirements

If required take a backup of all important data from your phone on an external storage device before proceeding.
Do not take a backup on the same device as some of these actions will format the device and delete the backup.
Ensure your phone is charged more than 50%
Check that adb and fastboot are enabled on your PC. If not you can find the setup instructions here
Download all the files and images mentioned in the download section below before starting the installation
Make sure you have a working data cable to connect your device to the PC. There are cables which are only for charging and do not transfer data.
Enable USB debugging on your device. You can find the instructions here
Make sure that your model is listed in the Smartphone Selector. Check the model supported. Where available, information on the model supported should show as a pop-up when you hover the cursor on the Device name. The model number supported should be the exact same.
Boot your device with the stock OS at least once and check every functionality.

Warning: Make sure that you can send and receive SMS and place and receive calls (also via WiFi and LTE, if available), otherwise it will not work on /e/OS as well. Additionally, some devices require that VoLTE/VoWiFi be utilized once on stock to provision IMS.

Please share your experience , suggest tips or changes to this install guide documentation by visiting the Mi MIX 2S specific topic on our community forum.

To report issues in /e/OS please refer this guide

Downloads for polaris

Before following these instructions please ensure that the device is currently using the firmware version mentioned below. If your current installation is newer or older than the required version, please upgrade or downgrade to the required version before proceeding by following this guide.

Download the required firmware for your model.

Mi MIX 2S China - V12.0.3.0.QDGCNXM
Mi MIX 2S Global - V12.0.3.0.QDGMIXM
Mi MIX 2S Russia - V12.0.2.0.QDGRUXM
/e/OS Recovery for community build
/e/OS build : T community

To understand the difference between /e/OS builds check this guide

Unlocking the bootloader

Tip: The steps given below only need to be run once per device.

Warning: Unlocking the bootloader will erase all data on your device! Before proceeding, ensure the data you would like to retain is backed up to your PC and/or an online drive

Warning: Some vendors/manufacturers prevent the bootloader from being unlocked. Depending on where your device was acquired you may or may not be able to unlock the bootloader. To verify if your device is compatible please check the devices list.

Tip: It is highly recommended to have the latest official MIUI dev package installed on the device, before proceeding with unlock.

Create a Mi account on Xiaomi’s website.
Add a phone number to your Mi account.
Insert a SIM into your phone.
Enable developer options in Settings > About Phone by repeatedly tapping MIUI Version.
Link the device to your Mi account in Settings > Additional settings > Developer options > Mi Unlock status.
Download the Mi Unlock app (Windows is required to run the app).
Run the Mi Unlock app and follow the instructions provided by the app. It may tell you that you have to wait up to 30 days. If it does so, please wait the quoted amount of time before continuing to the next step!
After device and Mi account are successfully verified, the bootloader should be unlocked.
Since the device resets completely, you will need to re-enable USB debugging to continue.

A Mi account is required to apply for permissions. You don’t need to re-apply for permissions to unlock new devices, but beware that one account is only allowed to unlock one unique device every 30 days.

Installing a custom recovery using `fastboot`

Before proceeding ensure you have downloaded the custom recovery from the link given in the Download section above
Connect your device to your PC via USB.
On the computer, open a command prompt (on Windows) or terminal (on Linux or macOS) window, and type:
```
 adb reboot bootloader
```
You can also boot into fastboot mode via a key combination:
- Lorsque l’appareil est hors tension
- hold Volume Down + Power. Keep holding both buttons until the word “FASTBOOT” appears on the screen, then release.
Once the device is in fastboot mode, verify your PC finds it by typing:
```
fastboot devices
```
Tip: If you see no permissions fastboot while on Linux or macOS, try running fastboot as root

Tip: Some devices have buggy USB support while in bootloader mode. If fastboot hangs with no output when using commands such as fastboot getvar .. , fastboot boot …, fastboot flash … try a different USB port (preferably a USB Type-A 2.0 one) or a USB hub
Flash a recovery image onto your device by typing
```
 fastboot flash recovery recoveryfilename.img
```
Replace the recoveryfilename with the name of the recovery image you downloaded in the previous section
Now reboot into recovery to verify the installation:
- Lorsque l’appareil est hors tension
- hold Volume Up + Power.Keep holding both buttons until the “MI” logo appears on the screen, then release.

Steps to install /e/OS from recovery

Tip: Use the volume keys to navigate and power key to select

Tip: Use the volume up key to choose the arrow at the top to go back to main screen

Tip: If your PC is unable to detect your device with adb in the /e/OS recovery main screen tap Advanced » Enable adb

Format the device

On /e/OS Recovery main screen:

Select Factory reset
Select Format data / Factory reset option
Next screen will display a warning that this action cannot be undone
Select Format data to proceed or Cancel if you want to go back
If you selected Format data, the format process will complete

Tip: You will see text in small font on the lower left side of the screen mentioning format progress

The small font text would be similar to this
```
 Wiping data
 Formatting/data
 Formatting/cache
 Data wipe complete
```
Display will now return to the Factory Reset screen

Install /e/OS

In /e/OS recovery main screen:

Select Apply Update and in next screen Apply update from adb
In the next screen, the device is now in sideload mode

Note at this point the Cancel option is highlighted that does not mean you have canceled the action. The device is in adb sideload mode.
On your PC type begin adb sideload. Type the below command in a console

adb sideload downloaded_file_name.zip

Replace downloaded_file_name.zip with the name of the /e/OS file you downloaded in the previous section
Press enter key on the keyboard to start the sideloading The screen will show the progress percentage…This might pause at 47%
Give it some time
The PC console will now display Total xfer: 1.00x
The phone screen will now display some text with a message similar to

Script succeeded result was [1.000000]

This means that the install was successful.

Reboot the device