Saturday, December 31, 2011

How to unlock Samsung Galaxy S2 AT&T SGH-i777

Last post of the year 2011!

The following is a step by step guide to unlock AT&T Samsung Galaxy S2 (Attain) to use on All GSM carriers including T-Mobile. It is fairly long process but I have verified every step on Android 2.3.4 and it had worked for me. It should work for you too. This is the easiest method i've found and it does not require you type or modify files manually. So it's safest and you will be unlikely to brick the phone.

  1. Check whether your phone is already unlocked or not. Follow the steps here.
  2. Check whether Your Samsung Galaxy S2 is on Android 2.3.4. You may find it in the Settings->About Phone menu. If not, please restore to the stock rom 2.3.4 in order to root the phone. You may follow this guide to restore to stock rom.
  3. If it is not unlocked. Download and install superoneclick to root the phone. You can download the tool from here.
  4. Reboot the phone.
  5. Now go to Marketplace download and install the busybox Installer by Stericson. Run it to install busybox.
  6. Now go to Marketplace download and install the app Galaxy_S Unlock by Helroz. Follow the steps in the app to unlock. 
  7. Now your phone should be unlocked. You can verify whether the phone is unlocked with steps described in #1.

Note: If the anything goes wrong. You may hard reset the AT&T Samsung Galaxy S2 and start over.


Leave a comment if it works for you!


  1. It is a good methods to unlock samsung mobiles.....
    In this way i like to share my experience in unlocking samsung mobile........i unlock my samsung mobile through this site , here it gives the unlock code along with easy instructions for my mobile.......

  2. Iphone well to valuation of devices. Sound make it effective and crazy for better uses. It increase perfect to device valuation and uses.

  3. Free unlock Galaxy S -

  4. if i factory reset my unlocked galaxy s2 sgh-i777 will I loose the "unlock"????

  5. Hi,
    You can unlock your iPhone 4 by remote unlocking, it is both simple and safe. A lot of websites offer this unlocking service. I unlocked my iPhone at, and found their service and support to be good. You can have a clear idea on how to unlock your iPhone using remote unlocking at…; this site gives you free instructions on how to unlock cell phones!!

  6. I have found the post very useful and informative. Thank you for sharing this one. I'll continually be coming on a regular basis you just read your posts.
    Dell Laptops