(Important Note: Check the Baseband version of your phone. Go to Menu > Settings > About Phone. It should be I777UCKH7, I777UCKK6, I777UCLE5, I777UCLK3, or I777UCLL6 before updating. It will be I777UCMD8 after the update. But be advised that everything written here are only tutorials for Samsung Galaxy SII I777 AT&T. I’m not held responsible for any loss or damage of your Smartphone. Make sure you have an Internet Connection to complete the whole process. For Windows User/PC only.)
RULE OF THUMB: READ AND FOLLOW THE INSTRUCTIONS CAREFULLY
WHAT YOU NEED TO PREPARE:
* Before you apply an update, Backup necessary user data/files (such as pictures, videos, music, contacts, etc…) using Samsung Kies or any third party backup app.
* Check the current Software version, to do that, go to Menu – Settings – About Phone. See the Baseband Version. It should be I777UCKH7, I777UCKK6, I777UCLE5, I777UCLK3, or I777UCLL6.
* Download and extract Samsung USB Driver for Mobile Phones (click here) or Download and install Samsung Kies Software (click here).
* Enable USB Debugging (Settings – Developer options – USB Debugging)
*Make sure no (stop) anti-virus running on your PC/Laptop nor to your phone, this may interrupt the updating process.
*Make sure you have enough battery power on your device.
* Download and extract Official SGH-I777 Galaxy SII AT&T I777UCMD8 firmware (click here – LINK1)
THERE ARE TWO WAYS (using Samsung Kies and Manual Update via Odin Flash Program):
USING SAMSUNG KIES:
1. Download, Install and Launch Samsung Kies (You may launch it as normal or lite mode). Then connect your Galaxy SII (device) to your PC/Laptop USB port using USB cable. It should be detected by your Samsung Kies.
2. When Samsung Kies recognized your device, you will able to see a pop-up message. Click Update.
3. Read the pop-up message, click/check (I have read all the above information) and the Allow saving of information (you may chose/click Allow saving or Proceed without saving). After that, click Start Upgrade.
4. The firmware upgrade downloading begins (, do not close the application, nor shutdown you’re PC/Laptop, disconnect your internet connection nor your mobile device.
After the download, firmware begins the download to your mobile device. (You will see the Android logo and the message “Downloading…” Do not turn off target !!
You will see the message in your PC/Laptop.
5. After the firmware download/upgrade to your Galaxy SII (mobile device). You will see a message that your Firmware upgrade is complete. Click OK. It will restart after the firmware update.
Now you already update your Samsung Galaxy SII AT&T to a new firmware I777UCMD8 Android 4.1.2 Jelly Bean and ready to use.
USING MANUAL UPDATE VIA ODIN FLASH PROGRAM:
(Note: Use this only if you’re unable to perform firmware update using Samsung Kies for some reasons.)
1. Download and extract Official SGH-I777 Galaxy SII AT&T I777UCMD8 firmware – As mention earlier (see the above section for the download link).
2. Download and extract ODIN (v3.06) Flash Program (click here) or ODIN (v3.07) Flash Program – As mention earlier (see the above section for the download link).
3. Turn off your device (Galaxy SII).
4. Boot your device into Download Mode. (How to do it – click here)
5. After your device is in Download Mode. You can now launch the ODIN Flash Program that you download earlier. Connect your device to your PC/Laptop.
6. After you’re device is detected. (You will see a message “Added!!”) Click PDA Button afterwards that you’re device is detected and all set. (Note: Don’t not change any settings on ODIN, leave everything as is, and just make sure the Re-partition remains uncheck.)
7. Browse to the folder where you download and extract the Official SGH-I777 Galaxy SII AT&T I777UCMD8 firmware. Select it and click Open.
8. Click Start Button to begin the process, and wait the ODIN Flash Program to finish the installation of the new firmware.
9. After the installation, your device will reboot and you can now unplug the USB cable to your PC/Laptop and to your device. (Note: Samsung Boot Animation will take a few minutes on loading/updates.)
FAQ: What if the new firmware doesn’t boot to my device (Galaxy SII)?
Don’t worry and panic, it happens for some reasons, likewise there is a solution to that issue.
*Power off your device
*Boot to Recovery Mode (How to do it – click here)
* Select Wipe data/Factory reset (select and confirm it, use the volume keys as navigation and power button as confirm)
*Go back to Main Recovery Menu then select Reboot system now
*Wait for it (maybe several minutes), until it loads up the new firmware (Android Jelly Bean 4.1.2) on your device.
(Disclosure: Samsung (Galaxy SII AT&T, Samsung Kies, Drivers) / Odin Flash Program / External Links – Info/Logo/Images/Video/Pictures stated above has a respective copyright. We used it for demonstration purpose only.)
If something in your mind to comment or suggest, please let us know. In our efforts to provide detailed information, there is possibility of inaccurate contents. If you see any mistake or incomplete in our information, please don’t hesitate to tell us. We will fix it immediately as soon as possible.
Related Links / Articles / Entries / References / Sources:
Samsung Galaxy SII AT&T Gallery Images, Features, Specifications by Jcyberinux
Screenshots and details about New firmware I777UCMD8 for Samsung Galaxy SII AT&T by Jcyberinux
Taking Screenshot on Galaxy SII AT&T (SGH-I777 or Attain) by Jcyberinux
Download Mode for Galaxy SII AT&T (SGH-I777 / Attain) by Jcyberinux
Recovery Mode for Galaxy SII AT&T (SGH-I777 / Attain) by Jcyberinux
Samsung Android USB Driver for Windows – Samsung Developers – Official Site
Samsung Kies – Support – Official Site
Latest ODIN (Flash Program) – xda developers – Official Site
Samsung Galaxy S II AT&T Android 4.1.2 Jelly Bean Upgrade – Official Site