- First you will have to Download Odin 3 v1.85. This will be used to flash the TWRP image. You will need to be really careful while using Odin.
- Now you have to download TWRP 18.104.22.168.
- Make sure Kies is not running and that you have the USB drivers for Galaxy S2 installed on your PC.
- Extract the content from Odin 1.85 and run the program.
- When Odin will be opened, you will have to check the "auto-reboot" checkbox in the left upper side of the window. That's it. Make sure anything else is not checked. Especially make sure "re-partition" is NOT checked.
- Click on PDA, you will see this buttons in the right lower side, and add the TWRP 22.214.171.124 file you downloaded at step 2.
- Now you have to enter Download Mode on your phone. First connect the USB cable to the PC but not to your phone. Now remove the battery from your phone and insert it back. Press Volume up + Volume down simultaneously. While holding the buttons pressed, connect the USB cable to the phone. You should be prompted with a yellow triangle that tells you installing Custom ROMs is dangerous. Release the Volume Keys. To enter Download Mode press Volume Up once.
- Once you enter Download Mode, Odin should recognize your device.
- If you've done everything correctly, you should now be able to press Start in Odin and wait until it installs TWRP.
What's my model number?
There are several ways to locate your model number:
- Option 1
- On your device, go to Settings, then "About device" and scroll down to "Model number"
- Option 2
- Often times you can view the model number inside the device, by removing the battery
- Option 3
- Using Samsung's model/serial number location tool