1)Follow the instructions carefully. This tutorial is applicable for Galaxy S Advance phone (GT-I9070) running Jelly Bean Android 4.1.2 OS.
2)Make sure you’ve charged your phone to its full capacity.
3)Backup all contents on your phone including contacts, messages, apps (if you want to), images, videos, personal files as downgrading process will wipe everything.
4)Proceed at your own risk as your device might get bricked. So, do not downgrade unless you desperately want to. If you really want to downgrade to GB, you can even approach Samsung Mobile Service center to do the job for you instead of taking risk yourself. The author and this website hold no responsibility for any damage.
5)USB Data Cable
How to Downgrade JB 4.1.2 to GB 2.3.6 on Galaxy S Advance:
1)Download this package from (http://devhost.xda-developers.com/sA3) just copy and paste the link on ur address bar.
2)This is compressed file. Use 7-zip or winrar program to extract the archive.
3)Open Odin3 v1.85 version.
4)Turn off your phone. Go to download mode on your phone by pressing volume down + home+ power keys together. You’ll be asked to press volume up key to confirm entry into download mode.
5)Connect your phone to computer via usb cable.
6)In ODIN, a box will turn colored with com number and in the log window, there will be a message – Added.
7)Now click on PDA button in ODIN and select CODE_GT-I9070_I9070DXLD1_CL1068093_REV00_user_SEC_KEY_LD1_ 8G.tar.md5 file.
8)Now hit on CSC button and select CSC_GT-I9070-MULTI-CSC-OLBLD1_SEC_KEY_8G.tar.md5 file.
9)Hit on PIT button and select the PIT file extracted from the downloaded package in first step above (GT-I9070_EUR_XX_8G.pit).
10)Now, make sure Re-Partition, Auto-Reboot, F. Reset Time boxes are ticked in ODIN program.
11)Click on Start button.
12)Let the flashing process continue.
13)After some time, your phone will reboot. It might take time to start so have patience.
14)Once your phone starts successfully and ODIN displays PASS message in Green colored box, you can then unplug your phone from computer.
15)Go to phone settings to confirm if you’re successfully back on GingerBread OS.
(note:the below steps are only for 16gb s advance users)
16)Now, if you’ve 16GB Galaxy S Advance phone, your internal memory might have shrunk to much smaller size.
17)it must have now shrunk to 3.9gb from 11.5 gb
18)to fix this,just download your country's official GB from here(http://forum.xda-developers.com/show....php?t=2014516).
19)using odin 3.07,flash the official GB with auto-reboot and f.reset time ticked and RE-PARTITION UNTICKED(it should NOT be selected)
20)after flashing(go to-settings--->storage----->Format USB storage)
21)congrats,nw ur phone is perfectly running on official gingerbread(2.3.6)
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