The following is a step by step process of restoring the Samsung Galaxy S II (AT&T Attain I777) to stock ROM. Sometimes a factory reset does not fix the issue with the phone. You will then need to perform a restore to stock ROM to fully recover it. Or if your phone is bricked during flashing, restoring to stock ROM may also fix the issue. I have personally tried the below steps and it worked for me.
- Make sure Samsung USB driver is installed on your PC
- Download and unzip the file on your desktop
- Extract and run the file (run as administrator if you are on Windows 7)
- Put the phone in download mode (Hold both volume keys and then connect to PC with USB cable)
- Odin will should detect the phone in several seconds and show a yellow bar with com port number
- Press start and it shall progress and then reboot the phone. Once it's done, odin will show a green bar with "passed" and the phone will reboot
- Congratuations, now you just flashed the phone to stock ROM
Leave a comment if it works for you!