You may wish to unroot Galaxy S3 and restore back to the original stock ROM. Well, this page will give you a clear outline on how to do this. Before you proceed, remember that
You may face a bricking problem if you don’t follow the steps as outlined
Guidelines for unrooting Samsung Galaxy S3:
Before getting started, make sure that you have everything set ready. Check and ensure that you have these set in place.
Make sure you have charged to over 70%. This is because if you are short of power and you get shut down during the operation, then you will most definitely get bricked. The same should also apply to your computer, preferably being plugged in during this process.
Install USB drivers for your on your computer. Always make sure to have the drivers that support your model, and it is always recommended to update to the latest drivers for best results
Ensure that you created a backup of your content in case the process fails to go through.
Checking model Number
Always make sure that you know your number as this is meant for the i9300 only. Thus, to check, follow these steps
– Tap Settings then look for About Device and tap it.
– Now you will see Model Number. That is the number you need to know.
Have the native USB data cable ready. Along these lines, ensure that you have enabled Debugging Mode.
Enabling USB debugging:
If you haven’t already enabled debugging mode, then you may do so by following these steps.
Go to settings and look for then tap on About Phone.
Scroll down to Build Number and tap this 7 times and make sure you receive a notification that you are now a developer then go back to the settings main menu.
Scroll down and tap the now available Developer Option and tap this and on the new interface, look for Enable USB debugging and tap this. That is it.
Now that you have everything ready, simply proceed with the rooting by doing the below.
Download the right stock firmware for your phone here and then you should extract the downloaded file on your computer to obtain the .tar.md5 file
Now download Odin3 v1.85 from this link then extract the downloaded Odin as well to a folder of your choice.
Now power off and reboot in Download Mode by holding Volume Down + Power + Home button at the same time. Now to be able to proceed, you should press Volume Up to proceed to Download
Mode or you may cancel by pressing Volume Down button if you wish to make any changes.
Now open the folder where you extracted Odin and run this as an administrator by Right Clicking on the Odin icon and selecting Run as Administrator. You should then plug in your device whilst in download mode and wait for Odin to detect it, by showing the notification Added.
Selecting your files
Now for this step, be CAREFUL. Do:
(Below, you may ignore steps 2, 3 and 4 if you cannot find the files specified in those steps)
Click PDA button and navigate to the folder that you extracted .tar.md5 file and select it
Click on phone-button and then select the file which has Modem
Next click CSC button and then choose the file which has CSC on its name.
Now you have to click on PIT button and pick the file which has the .pit extension.
Two settings have to however be checked. These are Auto Reboot and F.Reset. Also remember to un-check Re-Partition.
Note: The above step is important since if you don’t un-check the re-partition option, then you will actually be using the wrong settings for this operation, hence potential bricking risk.
Now click the Start button and wait for the whole process to complete. Suppose you followed all the above steps clearly, then you will see a green notification indicating PASS. Otherwise, you have to backtrack to a step that you may have made an error.
Make sure to check out my Galaxy S3 page for future updates.