HOW TO Downgrade And Jailbreak Iphone from 4.0 to 3.1.3

Download Link File http://filesharego.com/EleneMedine/Jailbreak 1. Plus the device into your USB cable with iTunes open and put the device into DFU mode. Once in DFU mode, iTunes will tell you that the device needs to be restored - press okay, and then Hold Option + Click Restore and navigate to your 3.1.2 firmware. 2. After device restores, you'll be hit with a 1015 error. This is expected, just leave iTunes running and launch blackra1n. Jailbreak as normal. NOTE: Once you begin blackra1n, you'll notice your device becomes blank, where normally you'll see Geohotz face, THIS IS NORMAL. Just leave the device alone for a minute or so, and then manually hold the power button down until the device shuts down completely. After a few seconds, power the device back on and you'll notice you are now on stock 3.1.2 (there will be no service on the device at this time) 3. After the device is powered back on, you can run blackra1n once more to jailbreak FW 3.1.2 (again, there will be no service). After the device reboots you should now be at jailbroken 3.1.2 with no service. 4. Now, close blackra1n and open up Pwnage Tool 3.1.5 and create a custom FW for 3.1.3 NOT 3.1.2. I suggest using the Expert Mode and unchecking hacktivation and boot logos. (they are cheesy anyway). 5. Once the Custom 3.1.3 FW is finished, launch iTunes, Hold Option + Click Restore and navigate to the Custom FW and allow iTunes to do it's damn thing. Once it's finished, you should happily be sitting on 3.1.3 jailbroken.