[T-Mobile, Samsung Galaxy SIII] elesbb:
This guide is a COMPLETE guide. Meaning, no matter what ROM you are on, how many flash counters you have, if you have any recovery flashed, in the end of completing this guide you will have a 100% Stock 4.1.1 device with a flash counter of zero and an Official status.

Prerequisites:

Obtain the following:

1. Odin found here on XDA

2. Latest Odin flashable Official Firmware ---- Found here in Dev section

3. Obtain Triangle away found here or google for the manual method.

4. Patience and the ability to follow directions :)

Now the work :)

If you are on any custom ROM WITHOUT a custom recovery and a ZERO flash counter. To check status, boot to download mode by doing:

1. Power phone off

2. Press volume down, along with the home button, then press the power button.

3. You should see a screen with a triangle on it. If you press volume up you will continue, if you press volume down you will reboot.

4. Press volume up. You should see in the top left a list of text look for "CUSTOM BINARY DOWNLOAD:" it will say no if its a zero flash counter. It will say "Yes" if its tripped.

5. Go ahead and power off the device by either removing the battery or pressing and holding the power button for approx. 10 seconds. (This will reboot)

Now if you have a flash counter of zero (no) then just follow the directions below, if you have a "yes" for custom binary download. Then skip these settings and continue reading.

1. Boot phone to download mode as mentioned above. (With phone off, press volume down, home, then power while holding all the buttons until it boots up)

2. Plug your phone into your computer with your data cable.

3. Launch Odin and select PDA button.

4. Find the downloaded official firmware and select it.

5. Select start and let it do its thing

6. When it is finished it will automatically reboot and you are done. :)

Now if your counter has been tripped AND you are on a custom ROM with root, then follow directions here:

(NOTE: This method works regardless if you have a custom recovery or not. All you need is Root)

1. Install Triangle away and use that to reset your flash counter. Or use the manual method.

2. After you reset your flash counter.

3. Double check that it is zero by booting to download mode.

4. After you confirm its zero plug your device into your computer

5. Using Odin flash your latest firmware (4.1.1 for T-Mobile)

6. You should be good then.

Now before anyone flips, stating there are other guides. Yes there are. I am just posting this Guide because a lot of people are confused as to if tripping the flash counter is irreversible and it is. Its just no longer a set it and forget it method. Meaning, you are only able to reset flash counter when you are ready to take your device into a rep to have them look at it to diagnose something. When i had ICS on my device, i flashed CWM and tripped the counter. So i grabbed Triangle Away and reset it and was good. now that i have my refurb device which had 4.1.1 pre installed, the only way to reset the flash counter is RIGHT before you flash the latest official firmware. If you follow this guide. then you should be good to go with warranty issues.

If you have any trouble just post in this thread.