Process of Rooting is something like to install a custom kernel on your device. It is pretty safe act that does not erase anything from your device. When you need to Root AT&T Galaxy S-II on UCALK3 Android 4.0.4 ICS Firmware then take the following measures as shown below.
Step 1. Rooting process needs to download Root CF-Auto Root for AT&T Galaxy S II and ODIN v3.07 one after another.
Step 2. Now, Turn Off your device and go for Download Mode. For this, press and hold Volume Down + Home Button altogether for few seconds followed by Power button to bring Android logo along with Triangle on Screen.
Step 3. Just after above act, open ODIN on PC and plug your AT&T Galaxy S II I777, using USB cable.
Step 4. When AT&T Galaxy SII I777 connects to PC, the ID:COM box turns yellow and display the COM port number.
Step 5. Navigate Downloaded file and click on PDA and select cwm-trebon.tar.md5 file to install.
Step 6. Press Start button in ODIN window to begin installation process, before this you need to check Auto Reboot and F.Reset Time option.
Step 7. The process of installation needs a few minutes. When it completes your device will restart automatically with new changes.
It should be noted, all such steps will be taken, once you assure about following arrangements have been made:
- Having installed USB drivers of AT&T Galaxy S II I777 device on your PC.
- Have efficient battery power. In any case, your smartphone device should not be less than 80% charge.
- You need to enable USB debugging mode that deactivates by default.
- Take backup of all important data stored in phone memory.
Note: Above mentioned measures is to be applied only on AT&T Galaxy S II I777 device. It can’t be effective for another model. Applying these settings on other devices could harm in many ways.