There are many reasons why you may want to return your Galaxy S to stock form.
You may want to sell it, or return, or send it in for repair. Perhaps you want it in a state where it can receive an official update. Or perhaps you just want to start from square one again, and get it back to the way it was when you first took it out of the box.
Returning a Samsung Galaxy S smartphone to stock configuration is fairly easy. You will need:
1. ODIN
2. A “Full” factory firmware package
3. The firmware package for the stock version you want to flash.
A Full firmware package contains 3 separate files for Odin. A PDA file, which contains the main Android operating system code, a PDA file which is the modem, and a CSC file which contains ‘Carrier Specific Customizations.’
Your starting point does not matter. It does not matter what custom ROM you installed, or what experimental kernel you had flashed. It does not matter what lagfixes you have enabled. It also doesn’t matter if your phone was rooted before or not.
The one thing that does not get affected is if your phone is SIM unlocked. If you unlocked it, flashing factory Samsung firmware via Odin will not re-lock it. If you do need to re-lock your phone that would be a separate task.
Once you have downloaded Odin and the firmware packages you need, the procedure is fairly simple. First flash the full firmware package with Re-partition checked, and the appropriate PIT file selected. After that, if necessary, flash the PDA file of the specific firmware version you want.
Here’s the Video:
Get Odin and find detailed instructions from XDA-developers:
ODIN Download from XDA
Download the Samsung factory firmware you want from www.samfirmware.com