How To: Unroot the Nexus S

I. Before You Begin

1. This will return the phone back to the stock ROM and put you at build GRH78.

2. Use this method to start over, or to send your phone in for warranty reasons.

3. You MUST have a custom recovery image to use this unrooting method.

4. This WILL WIPE everything on your phone.

II. Create a Nandroid Backup

1. Turn off your phone.

2. Turn it back on by holding down Volume Up and Power until the green Android shows up on the phone.

3. Using the volume buttons and power to select, select Recovery from the menu.

4. Once in recovery mode, select Backup and Restore then select Backup and wait for it to backup your current ROM.

5. Once it is done, select Reboot and wait for the phone to reboot.

III. Flash the Stock Nandroid Backup

1. Download the stock Nandroid Backup and save it to your computer.

Stock GRH78 Nandroid Backup

2. Extract the .zip file somewhere on your computer.

3. Plug your phone in via USB cable and mount the internal storage so we can transfer files to it.

4. Find the Clockword folder on your phone’s internal storage and open it, then open the Backup folder inside there.

5. Copy the 2010-12-22.21.06.07 folder from the .zip file you extracted and put it inside the Backup folder we just opened.

6. Turn off the phone.

7. Turn it back on by holding down Volume Up and Power until the green Android shows up on the phone.

8. Using the volume buttons and power to select, select Recovery from the menu.

9. Once in recovery mode, select Backup and Restore then select Restore and choose the  2010-12-22.21.06.07 backup and wait for it to restore the phone to stock.

10. Once it is done restoring, select Reboot and wait for the phone to reboot.

11. Once it does reboot, turn it off and then back on normally again (this is to clear out the recovery image and bring that back to stock as well).

IV. Relock the Bootloader

1. On the phone, go through the setup process clicking skip where ever possible.

2. Then hit Menu then Settings then Applications then Development and make sure USB debugging is checked ON.

3. Plug the phone in via USB.

4. Open a command prompt on the computer by clicking on the Start menu and typing cmd and hitting enter in the search bar.

5. Then in the command prompt, type the following with hitting enter at the end of each line (this is assuming you did our How To Root the Nexus S procedure):

cd\
cd c:\androidsdk\tools
adb reboot bootloader
fastboot oem lock

6. The phone should relock the bootloader and you are now fully stock and completely ready to send the phone in for warranty or go back to the How To Root procedure and reroot it.

  • Wackyfordrums

    will this work on GRJ22??

  • Giuseppe Carola

    Hallo! I’m sorry, i did everything this how-to says, but when I type fastboot oem lock I get an error message: “command fastboot is either wrong spelled or couldn’t be found” (something like that, not the exact words). Can you please help me? What should i do in this case?

  • LJ000110

    Worked for me, spot on, thanks!

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  • Abinash

    where i can get stock GRJ22 Nandroid backup??….plz help me

  • Spider

    I did this, and my phone got soft-bricked (i think). It was just booting into emergency calls mode. I was running GRJ22 before. Help.

  • Jason

    When I type in fastboot oem lock in fastboot mode, cmd just says waiting for device and nothing happens, i have made sure its in debug mode and everything, please help!

  • Mike K

    worked but my phone is stuck in airplane mode. when I disable it just goes back and I cant enter any apn info nor can I upgrade to 2.3.6.

    • Merry

      Hi r u able to fix ur phone??? M also facing smell issue NW :(… plsss helpp

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  • Anonymous

    I have managed to unlock my goog nexus s, but after that, the phone doesnt boot into recovery mode. It gives me a caution sign… don’t know what to do after this. 

  • Merry

    Hi I did everything as mentioned and it worked.. But my service is not connecting now. can u pls help me in this?

  • Simon Thomassen

    Fuck you bitch, just fucin made my phone go into locked mode FUCIN LOSER

  • Games1973

    the network does not work

  • Games1973

    i need help

  • Colex

    Hello, I need help in unroot my Nexus S… I accidentally unrooted my Nexus S with Nexus S 4G ROM and could not undo it ever since…… I tried your unroot method but it does not work… My screen just frozen….

  • doju_style

    be careful! I tryed to unroot from cynogen to the stock version provided in the tutorial and I lost 3 lights of the front panel and the screen became uncalibrated, I couldn t even enter my gmal account for initial setup. I had to go back to the previous restore to fix it.

    • Nik

      same probleme here, but i cant go back to my backup… because the warning with andorid symbol appears… :(…. i think i bricked my nexus s. can anybody help?

    • Nik

      same probleme here, but i cant go back to my backup… because the warning with andorid symbol appears… :(…. i think i bricked my nexus s. can anybody help?

    • Nik

      same probleme here, but i cant go back to my backup… because the warning with andorid symbol appears… :(…. i think i bricked my nexus s. can anybody help?

  • Camielnijpels

    so this completely restores your warrenty?

  • Lizabeth_starsinger

    prompt says cannot find path specified when typed in cd c:androidsdktools

  • http://www.facebook.com/twilighted.mac Mudassir Malik

    Thanks a ton David!

    I went through tons of posts but none of them worked..but yours did..:)
    Thanks again..stay blessed..cheers!

  • http://twitter.com/DontBeChp Dean John

    wouldve been awesome to know this was for I9020T and not I9020A a long time ago.