Install OkcarOS on
Samsung Galaxy Tab A 8.0 (2019)

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警告: The provided instructions are for OkcarOS 20. These will only work if you follow every section and step precisely.
Do not continue after something fails!

Basic requirements

Read through the instructions at least once before actually following them, so as to avoid any problems due to any missed steps!
Make sure your computer has adb and fastboot. Setup instructions can be found here.
Enable USB debugging on your device.
Make sure that your model is actually listed in the “Supported models” section here (exact match required!)
Boot your device with the stock OS at least once and check every functionality.
LineageOS is provided as-is with no warranty. While we attempt to verify everything works you are installing this at your own risk!

Special requirements

警告: Your device must be on bootloader version T290XXU3CVG3 , otherwise the instructions found in this page will not work. The current bootloader version can be checked by running the command getprop ro.bootloader in a terminal app or an adb -d shell from a command prompt (on Windows) or terminal (on Linux or macOS) window.

Pre-Install Instructions

警告: The following instructions will unlock the bootloader and wipe all userdata on the device.

Connect the device to a Wi-Fi network.
Enable Developer Options by pressing the “Build Number” option at least 7 times, in the “Settings” app within the “About” menu
- From within the Developer options menu, enable OEM unlock.
Download this package.
警告: If you skip this step, you will not be able to unlock your bootloader!
Power off the device, and boot it into download mode:
- With the device powered off, plug in the device while holding Volume up + Volume Down + Power.
- Now, click the button that the onscreen instructions correlate to “Device unlock mode” and/or “Unlock Bootloader”.
- Device will restart, repeat steps 1 and 2 to enable the Developer Options menu again.
- Verify that “OEM Unlock” is still enabled and continue to step 5
Download and install the necessary drivers.
- Download the newest Samsung drivers from here.
- Install SAMSUNG_USB_Driver_for_Mobile_Phones.exe.
Download this version of Odin.
Extract “Odin_3.13.1.zip”.
Run Odin3 v3.13.1 found in the newly extracted “Odin_3.13.1” folder.
Check the box labeled next to the button labeled “BL”, and then click the “BL” button.
- In the menu that pops up, select the previously downloaded package .tar file.
Power off the device, and again boot it into download mode:
- With the device powered off, plug in the device while holding Volume up + Volume Down + Power.
Check in the top left of the Odin window that you see a valid device, it will show up as something like COM0.
Tip: The COM port, or the number succeeding COM, may be any valid number.
Click “Start”. A transfer bar will appear on the device showing the package being flashed.
Your device will reboot, you may now unplug the USB cable from your device.
- After this step, your bootloader version will display as T290XXS3ATF1. This is a part of the bootloader unlock process.
警告: If, on this step, your device is stuck on a black screen, your device’s bootloader is not unlockable and you cannot continue with these instructions. To return to the stock ROM, boot to Download mode and flash the BL package here.
The device will demand you format userdata, please follow the onscreen instructions to do so.
Run through Android Setup skipping everything you can, then connect the device to a Wi-Fi network.
Re-enable Development settings by clicking the “Build Number” option 10 times, in the “Settings” app within the “About” menu, and verify that “OEM Unlock” is still enabled in the “Developer options” menu.

Important Information

注意: The following instructions require a machine running Windows 10 build 17063 or newer.

Samsung devices come with a unique boot mode called “Download mode”, which is very similar to “Fastboot mode” on some devices with unlocked bootloaders. Odin is a Samsung-made tool for interfacing with Download mode on Samsung devices. The preferred method of installing a custom recovery is through Download Mode – rooting the stock firmware is neither necessary nor required.

Installing a custom recovery using `Odin`

注意: If this device’s install instructions already had you download Odin/Enable OEM Unlocking earlier in the installation process, you can skip the steps for enabling OEM Unlock, as well as for downloading and extracting the drivers and Odin.

Enable Developer Options by pressing the “Build Number” option 10 times, in the “Settings” app within the “About” menu
- From within the Developer options menu, enable OEM unlock.
Download Lineage Recovery. Simply download the latest recovery file, named recovery.img
Open a Command Prompt in the folder where the file was downloaded, and TAR the file by running tar --format=ustar -cvf recovery.tar recovery.img.
Tip: Make sure to not accidentally name the file recovery.img.img when file name extensions are hidden.

Tip: You can open a command prompt in any folder by right-clicking on empty space while holding Shift and selecting “Open Command Prompt here” or “Open PowerShell window here” from the context menu.

Important: Other recoveries may not work for installation or updates. We strongly recommend to use the one linked above!
Power off the device, and boot it into download mode:
- With the device powered off, plug in the device while holding Volume up + Volume Down + Power.
- Now, click the button that the onscreen instructions correlate to “Continue”, and insert the USB cable into the device.
Download and install the necessary drivers.
- Download the newest Samsung drivers from here. You will need to create a Samsung account and login to download them.
- Install SAMSUNG_USB_Driver_for_Mobile_Phones.exe.
Download this version of Odin.
Extract “Odin_3.13.1.zip”.
Run Odin3 v3.13.1 found in the newly extracted “Odin_3.13.1” folder.
Check in the top left of the Odin window that you see a valid device, it will show up as something like COM0.
Tip: The COM port, or the number succeeding COM, may be any valid number.
In the left side of the Odin window, you will see an “Options” tab, click it, and then un-check the “Auto Reboot” option.
Check the box labeled next to the button labeled “AP”, and then click the “AP” button.
- In the menu that pops up, select the newly downloaded (or built) custom recovery .tar or .tar.md5.
Tip: The filename may vary depending on your device, and the version of your custom recovery.
Click “Start”. A transfer bar will appear on the device showing the recovery image being flashed.
注意: The device will continue to display Downloading... Do not turn off target!! even after the process is complete.
Unplug the USB cable from your device.
Manually reboot into recovery, this may require pulling the device’s battery out and putting it back in, or if you have a non-removable battery, press the Volume Down + Power buttons for 8~10 seconds until the screen turns black & release the buttons immediately when it does, then boot to recovery:
- With the device powered off, hold Volume Up + Power.
注意: Be sure to reboot into recovery immediately after installing the custom recovery. If you don’t the custom recovery will be overwritten on boot.

注意: If your recovery does not show the OkcarOS logo , you accidentally booted into the wrong recovery. Please start at the top of this section!

Installing OkcarOS from recovery

Download the OkcarOS installation package that you would like to install or build the package yourself.
- (Optionally): If you want to install Google Apps add-on package (use the arm64 architecture), you can download it from here.
If you are not in recovery, reboot into recovery:
- With the device powered off, hold Volume Up + Power.
Now tap Factory Reset, then Format data / factory reset and continue with the formatting process. This will remove encryption and delete all files stored in the internal storage, as well as format your cache partition (if you have one).
Return to the main menu.
Sideload the OkcarOS .zip package but do not reboot before you read/followed the rest of the instructions!
- On the device, select “Apply Update”, then “Apply from ADB” to begin sideload.
- On the host machine, sideload the package using: adb -d sideload filename.zip.
  Tip: Normally, adb will report Total xfer: 1.00x, but in some cases, even if the process succeeds the output will stop at 47% and report adb: failed to read command: Success. In some cases it will report adb: failed to read command: No error or adb: failed to read command: Undefined error: 0 which is also fine.

Installing Add-Ons

注意: If you don’t want to install any add-on (such as Google Apps), you can skip this whole section!

注意: Add-ons aren’t signed with OkcarOS’s official key, and therefore when they are sideloaded, Lineage Recovery will present a screen that says Signature verification failed, this is expected, please click Continue.

警告: If you want the Google Apps add-on on your device, you must follow this step before booting into OkcarOS for the first time!

Click Apply Update, then Apply from ADB, then adb -d sideload filename.zip for all desired packages in sequence.

All set!

Once you have installed everything successfully, you can now reboot your device into the OS for the first time!

Click the back arrow in the top left of the screen, then “Reboot system now”.

注意: The first boot usually takes no longer than 15 minutes, depending on the device. If it takes longer, you may have missed a step, otherwise feel free to get assistance.

Get assistance

After you’ve double checked that you followed the steps precisely, didn’t skip any and still have questions or got stuck, feel free to ask on our subreddit or in #OkcarOS on Libera.Chat.

Install OkcarOS on Samsung Galaxy Tab A 8.0 (2019)