How To Install Official Android Lollipop On At&t Galaxy S5 G900A & Keep Root


AT&T Galaxy S5 has joined the Lollipop squad. Samsung started rolling out the OTA based on Android 5.0 Lollipop for this device. As expected, it carries some major changes. The most prominent changes are in the UI department. Samsung TouchWiz has been revamped according to Google’s new Material Design UI. New UI is pretty smooth and eye-soothing, a flat design has been adopted by Google for the elements on the screen. New notifications on the lock screen, guest modes, priority modes and a lot more is there to check out which makes this upgrade worth installing.

It took quite a while for this update to roll out for At&t Galaxy S5 SM-G900A. When the At&t Galaxy S5, it was quite impossible for the developers to come up with a method to root this device and get a workaround for its locked bootloader. After months of hardwork, GeoHot came up with his TowelRoot application that rooted plethora of devices alongside the At&t Galaxy S5. This just explains how hard it may get for carrier branded device users and specifically At&t device users to get beyond the boundaries. The exploit worked on Android KitKat only and many of the Android power users have been enjoying the sweetness of KitKat as well, but they sure would love to try something new and different that is available in the Lollipop update. But before you make a move towards Lollipop, you would tend to make sure if your device’s life is going to be the same as it was on Lollipop. The answer is No. If you simply update your device to Android 5.0 Lollipop straight away, you will lose root access and you won’t be able to root the firmware easily after updating. You can either update to pure stock OTA update and wait for a root method to come up, or you can use a different approach to update your device in such a way that you do not lose the existing root of your device, or through some means you can flash a pre-rooted firmware on your At&t Galaxy S5.

The good news is, all of the approaches listed above are possible. In the on-going post we will be going through three different methods that will help you to install completely pure and stock Android 5.0 Lollipop through stock recovery of your device, a pre-rooted Lollipop firmware using Chainfire’s all new FlashFire and restore a pre-rooted firmware using Safestrap Recovery.

  1. Let’s go through some quick early preparations and then begin updating the device.
  2. This method is only for At&t Galaxy S5  G900A running Android 4.4.2 or 4.4.4 KitKat. Do not use this method if your device is already on Android 5.0 Lollipop. Check your device’s software version and model number in Settings > System/ General / More >  About Device.
  3. Make sure that your device’s battery is charged at least over 60%. This is important to avoid any power issues during the installation process.
  4. Make sure that you’ve already backed all of your important contacts, call logs, sms messages. Also backup your important media content.
  5. Do not forget to backup EFS of your Galaxy S5. We also recommend backing up Nandroid if you’ve flashed Safestrap recovery on your device. [Only if you wanted to install pre-rooted firmware, otherwise skip this step.]
  6. Non of these methods will void the warranty of your phone or trip the Knox counter. Follow the instructions carefully, and make sure that you do everything on your own responsibility. In case a mishap occurs, we or the device manufacturers may not be held responsible.


How To Update At&t Galaxy S5 To Stock Android 5.0 Lollipop [No Root – Pure Stock]

  1. Make sure that you followed all the instructions listed above.
  2. For this method, your device must be running on Android  4.4.4 KitKat.
  3. Download Android 5.0 Lollipop Stock file and copy it to your phone’s external SD card.
  4. Now boot your At&t Galaxy S5 into recovery mode. To do so, turn off your device completely. Now turn it on by pressing and holding Volume Up + Home Button + Power Key. As soon as your device boots up, release the keys. You should be able to see the recovery mode now.
  5. Using the Volume Keys, navigate to “apply update from external storage” and press Power Key to make selection.
  6. Now select the Android 5.0 Lollipop file and then select “Yes” to proceed with the installation.
  7. Now wait for a few minutes till the update installation comes to an end.
  8. Once it ends, reboot your device. First reboot may take up to 10 minutes, hold on tighter in the meanwhile.
  9. That’s all! Your device is running on Android 5.0 Lollipop now 🙂 Enjoy!

How To Update At&t Galaxy S5 To Pre-Rooted Stock Android 5.0 Lollipop Using FlashFire

Your device must be rooted for this process. Make sure that your device is rooted. You can root it using TowelRoot.

  1. InstallFlashFire app, you must follow these steps to installFlashFire.
    1. Join Android-FlashFire community on Google+.
    2. Now open FlashFire Google Play Store link and hit “Become a beta tester”.
    3. It will take you to the installation page now, you can install it easily.
    4. You may install it using the FlashFire APK if you’re having difficulties with the procedure explained above.
  2. Now download the firmware file G900A_OC4_Stock_Rooted_ROM_wOA1_BL.
  3. Copy the downloaded .zip file to your phone’s SD card now.
  4. Now open the FlashFire App that you just installed on your device.
  5. Tap “Agree” to terms and conditions and allow the application for root privileges.
  6. Tap the “+” button twice in the lower right corner of FlashFire in order to bring up the actions menu.
  7. Now tap “Flash OTA or Zip” and select the file. FlashFire will now scan the file.
  8. In the next screen, leave the Auto-mount option un-checked and press the tick mark on the top-right corner.
  9. Do not touch anything else, follow these instructions to the letter.
  10. Once you’re done with all this, you’re good to go now. Tap the “lightening” button on the lower-left corner now.
  11. That’s all. Sit back and wait for the application to do the job. It will take around 10-15 minutes for your device to reboot and it will be running on rooted Android 5.0 Lollipop.

How To Update At&t Galaxy S5 To Pre-Rooted Stock Android 5.0 Lollipop By Restoring Backup In SafeStrap

  • Your device must be rooted for this process. Make sure that your device is rooted. You can root it using TowelRoot. Also install Safestrap if you want to install pre-rooted firmware.
  • Enable USB debugging mode on your At&t Galaxy S5.
  • Download Odin3 on your PC.
  • Use stock data cable to establish connection between your device and your PC.

Install Instructions:

  1. Now download the firmware file, G900A_OC4_Stock_Rooted_Backup.rar and extract it.
  2. Also, download the partitions file: G900A_OC4_Stock_Partitions_wOA1_BL.tar.md5
  3. Now copy the extracted files the Backup folder on your phone’s SD card. This is the Nandroid Backup folder, that you created using Safestrap recovery, the path should be as “ext-sdcard/TWRP/BACKUPS/abc”. Just in case you couldn’t find any such folder in the external storage, you can simply boot into SafeStrap recovery, tap the Backup option and create a backup. This will create the folder in your phone’s SD card and you can copy the extracted file after this.
  4. Now boot into SafeStrap recovery once again and tap “Wipe”. Wipe everything except your external SD card.
  5. Now go back to the main menu in SafeStrap recovery and tap the “Restore” option. Restore the G900A_OC4_Stock_Rooted_Backup file.
  6. Once this file is flashed, tap the “Reboot > Download” mode option in the SafeStrap recovery. Your device should be in the download mode now.
  7. Now open Odin3 on your PC.
  8. Connect your At&t Galaxy S5 to your PC. Your phone should be in the download mode already. Odin3 will turn blue once it has detected your device.
  9. Now click on the “AP” tab in Odin3, if you’re using an older version of Odin, you will click on the “Modem” tab. Make sure that all options except F.Reset Time are unticked in your Odin3.
  10. Select the G900A_OC4_Stock_Parititions_wOA1_BL.tar.md5 file.
  11. Click on the “Start” button now and sit back while it flashes the file.
  12. Once flashed, disconnect your device and reboot it manually now.
  13. First boot may take up to 10 minutes, once your device boots up completely, it will be running on Android 5.0 Lollipop.
  14. That’s all, Enjoy 🙂

That’s it. We hope that you found the methods easy. Just in case you get stuck with something, do not hesitate to catch us up through the comment box below. Thank you all.

Usama is a software engineer by profession and at he uses his expertise to solve everyday consumer tech problems with his main areas of interest being Android, iOS and Windows.


  1. @usamamujtaba:disqus My firmware is kitkat 4.4.2 and the method is from de SD CARD (Apply update from sd)

  2. @disqus_MHqaaWYRSB:disqus the safestrap method is not working anymore because of files. However, using the flashfire method, I’m not sure if it will let your recovery stick to the device or not. So I’m not sure if you will be able to create and restore backup or not.

  3. I’m running 4.4.2 on my SM-G900A (KOT49H.G900AUCU2ANG3), would this update work for me? I’ve downloaded and put the .zip file on my SD card and when I select it in recovery mode it loads the update but then goes back to the main menu?

  4. @mauriciojosueareasperez:disqus Did you make Nandroid backup? If so, then restoring it will fix your device.
    Otherwise flash latest stock firmware using Odin to recover your device now.

    • I had someone tell me if the FireFlash method fails you cannot restore with a Nandroid backup and you can’t Odin back to stock. Is this true?

  5. @fernarvaez:disqus for now you can use the alternative method. Not working links will be updated as we find those links. Thanks

    • Thank you for your help, but it seems that the uploader took it off, because it says not found.

        • Already tried this method, doesn’t work on my phone: SM-G900A – Galaxy S5 (AT&T) – Firmware 4.4.2
          Got stuck on bootload.

          • @djeanantunes:disqus Can you please tell me briefly what you exactly did?
            I’m not sure yet what went wrong with your installation.

          • I installed FireFlash and towelroot, rooted it with towelroot, then downloaded G900A_OC4_Stock_Rooted_ROM_wOA1_BL, put in the sd card, executed Fireflash, choosing Flashzip or Ota to execute the rooted rom above. I had already enabled usb debbuging and unknown sources. Adjusted the order in fireflash, first wipe and then flashing. After Fireflash finished flashing, it showed that it was done, but then I got stuck on bootload. Put the phone on download mode, flashed G900A_Downgrade_to_NCE.rar using this method to bring it back. Tried this many times, trying to figure it out what I did wrong, always the same result.
            About to give it up

          • @djeanantunes:disqus Can you give it a try without selecting wipe option? Let me know if it still gives you bootloop. The bootloop is probably because of bootloader only. If this still doesn’t work, I’ll look into what’s wrong.

  6. Just updated my AT&T G900a s5 with lollipop now I want 2 root it,does anyone a method to root your phone and keep lollipop ,did worked b4 when I had kitkat 4.2,since then I cannot root,help!:(

    • Fortunately, yes.
      I searched for the solution everywhere and at xda forum someone gave me the solution, sideloading the files NCE to NGE and NGE to OA1, and then sideloading the 5.0.
      All went well and now my phone it’s on lollipop.
      Thank very much for your kindness and support

      • @djeanantunes:disqus Glad to know that you’ve recovered.
        I’m’ still looking into what’s wrong with this file… the method is provided by a developer

        • Thank you very much.
          This file worked with many people, maybe my phone is the diferente one, I don’t know
          For those who couldn’t update with it, I believe that the best thing to do is going to the other method, that worked with me.

  7. Hello guys
    My SM-G900A 4.4.2 no root no update. Android 5.0 Lollipop Stock it will work my phone?

      • You say “2. For this method, your device must be running on Android 4.4.4 KitKat” but your answer to @disqus_5qsouJX1fq:disqus is “yes it will work”. How’s that?

        My G900A runs 4.4.2. It’s unrooted, no updates have been installed. I just bought it from At&t (USA) but I’m using it in Greece with a Greek carrier.

        Are you sure I can follow the guide above?

        • @koctastzzz:disqus for flashing OTA, your device must be running the most recent previous update and for Lollipop, that is 4.4.4. Flashing OTA on 4.4.2 won’t work. You may use the 2nd method, that works on 4.4.2 and 4.4.4 as well.

  8. HI Usama, I have a Samsung S5 SM-G900A-from ATT company, I´m living in Monterrey, Mexico, and try to update de OS to Lollipop following the instructions for install the OTA step by step, in the last instruction say: whait about 5-10 minutes to come usable, have more than 45 minutes and the smartphone just feel hot and not start or turn on the screen. ¿What can I do? hope you can help me.

  9. @josecrodriguez:disqus Sorry for getting back late, I’m busy with my final exams at the moment.

    Has your issue been resolved already or you’re still having it? Please let me know.

    • Hi don´t worry, just remove the battery, turn on normal, and show the normal service in the latest version 4.4.2, finally can´t update. if you can help me to update, will be very gratefull

  10. @disqus_Mm4ovdsG6G:disqus you can root 4.4.2 and flash pre-rooted file. The link to root 4.4.2 is attached above. Sorry, I do not have the link for 4.4.4 currently.

  11. please help us with new links for method 2 and 3, im running android 4.4.2 on my S5 G900A and ive bin trying so hard to upgrade to android 5.0

  12. Hello,

    I have a Samsung Galaxy S6 SM-G900A from AT&T unlocked with OS 4.4.2 baseband G900AUCU2ANG3 , i currently live in Dominican Republic and want to update my galaxy to OS 5.0 Lollipop Stock non-root, what can i do?

  13. @usamamujtaba:disqus great tutorial! I have rooted and upgraded to lollipop and it works great. One thing though, Safestrap has been discontinued. Does it still work with lollipop or are g900A out of luck on custom recovery?

  14. my device is Galaxy S5 G900A AT&T , first i tried to root my device and after many times it failed but i got problem that it is now stuck on recovery mode (and USB Debugging seems deactivated ) and i tried to recover the lollipop for my devise using ODIN not succed , also KIES not recognizing my device so i couldn’t preform emergency firmware recovery , please advise me if somebody faced the same problem !

  15. please help me I have a galaxy s5 at & t version 5.1.1 android I try to make a profit downgrade my phone is brick. please help to unbrick my phone. i try many firmware but nothing please help

  16. I used your method and download to update a new s5 unlocked from KitKat 4.4.4 to stock (not rooted) lollipop 5.0. Did this relock the phone to at&t? I haven’t received my sim cards for new carrier but I notice a much bigger AT&T presence on the phone. wifi home page seems to be stuck on… Thanks for the help
    Edit 1/6/16
    Addendum: Got it sorted. I’m new to android. Everything looks good. Thank you for the upgrade and walk-through.

  17. Hi, greetings I have a Sasmung SM-G900A unlocked if I use the first method my cellphone wll be blocked againg? I read a lot users the cellphone locked againg when the cellphone finish the update thanks

      • Yeah sorry, let me explain better my question…

        I have a Samsung SM-G900A with Android 4.4.4 I want to update my Firmware up to Android L, but I can’t get the OTA update because I’m not AT&T customer

        My Cellphone is unlocked to all brands, if I use your first method on your guide I’ll lose my unlock? thanks

  18. @yangiangshum:disqus the firmware linked above is At&t exclusive, I’m not sure about the after effects of this firmware on your device. You should avoid it and install some custom firmware.

Got a question/query or a suggestion? Drop it below.