[Verizon Samsung Galaxy S III] andybones:
did you backup your IMEI after unlocking bootloader and rooting like suggested?

if so have you tried : adb reboot nvrestore

??

http://xdaforums.com/showthread.php?t=1852255

"Backup:

Part A (Samsung's built-in backup):

1. If your phone does not have Terminal Emulator installed, you will need to use ADB. Download and install the Android SDK platform-tools for your platform. This is a bit non-trivial as it requires the installation of the Android SDK, however, you can find a guide for installing adb here. After installing, open a command prompt and navigate to the "platform-tools" folder within the SDK, where adb is stored. If you need additional help on this, simply ask in this thread.

If your phone is rooted and has Terminal Emulator installed, you don't need to do any of this. Simply open up the Terminal Emulator and go to step 2.

2. For ADB: Connect your phone to the computer and ensure it is in "Debug Mode" (Settings->Developer Options->USB debugging). Then. in the command prompt, type the following:

Code:

adb reboot nvbackup

For Terminal Emulator: The actual "beef" of the command is the "reboot nvbackup" line. Therefore, if you have Terminal Emulator installed, you can just run the command straight off your phone. Enter these two commands from the app:

Code:

su

reboot nvbackup

3. Your phone will reboot and copy the contents of two IMEI partitions to the two built-in backup blocks. You may see tiny blue text on the bootloader screen indicating that it is copying.

4. Allow it to finish and then reboot back into Android. The "fsg" and "backup" block devices now contain your IMEI information as they should have in the first place.

Part B (SynergyROM's "Plan B" manual backup):

1. Download the attachment at the bottom of this post. This is an update ZIP you can run right from recovery.

2. Reboot into recovery. On stock this can be done by turning off the phone and then turning it back on while holding UP and HOME.

3. CWM: Use VOL UP and VOL DOWN together with HOME to select "install zip from sdcard" then "choose zip from sdcard". Navigate to the folder you downloaded it to (most likely Download/). Select the zip you just downloaded to "flash".

TWRP: Touch "install" and navigate to the folder you downloaded the zip to (most likely Download/). Swipe to confirm flash.

4. Allow the backup to complete successfully. "Flash" is a bit of a misnomer; this is actually just a script that will safely backup your EFS and radio information to /sdcard/synergyrom/backup without touching your ROM at this point. When the script completes, reboot.

Part C: Backup with QPST:

Once the gold standard of IMEI backup, this method (in my opinion) should now be done only in the event of an unlikely complete catastrophe where neither Samsung's built-in restore nor SynergyROM's restore works. Simply follow the instructions here for extreme peace of mind; you don't need to do this if you don't want to, but I personally did.

Restore:

Do not do this unless your IMEI has been lost!

Performing Part A of the backup should ensure that you never lose your IMEI in the first place; the theory being that the Samsung built-in backup now has a good image to restore itself, as opposed to a dummy image. However, things may still happen. If you've still lost your IMEI, perform each of these methods in order of priority, "A" being the first.

Restore Plan A:

Run the following command from adb, just like when you backed up (have Android SDK installed, connect phone, and ensure USB debugging is enabled):

Code:

adb reboot nvrestore

This method triggers Samsung's built-in IMEI restore; except this time, you got good images on your side. Simply allow the phone to restore and reboot itself when completed. NEVER PERFORM THIS COMMAND WITHOUT DOING PART A OF "BACKUP" FIRST; THIS WOULD RESTORE THE DUMMY IMAGES INSTEAD AND WIPE YOUR IMEI!

Restore Plan B:

Sometimes a fluke happens and the nvrestore does not work. That's why this one is Plan B and not Plan A. Good thing you did Part B of "Backup"! Rather than instructing Samsung's bootloader to restore your NVRAM, this method will do so manually from recovery using a manually done backup.

It's just like when you backed up, except now you want to flash the zip containing your NVRAM info that the other zip built for you. This zip is located in /sdcard/synergyrom/backup. Simply navigate to this path and flash the zip beginning with "keybackup"; this will write images to 5 block devices from a time when your IMEI was all good. Reboot the phone; if all went well, you now have your IMEI back with no roaming!

Restore Plan C:

Both methods above may fail you in extremely unlikely circumstances. At this point, you'll need to try using QPST to get your IMEI back. If you did Part C in "Backup", you can follow instructions in that same thread to get you back up and running. In most QPST restores, you shouldn't have any issues with data or roaming.

Restore Plan D:

The planets have lined up, the Cubs have won the World Series, and all three above methods have failed you in what is surely a sign of the apocalypse. Far more likely, though, is that you didn't have a backup of anything and your IMEI is gone for good. The good news is that you can still get your phone working; the bad news is that you'll be stuck on roaming and may have problems with data. You'll need to perform an "IMEI injection" which is a kludgy last-resort restore method that manually writes the IMEI to NVRAM; the link I provided in Part C of "Backup" will tell you how to do it."