Downgrade from iOS4 to 3.1.3 and jailbreak and unlock iPhone 3G

**omg** · 07-11-2010, 06:47 PM

Have you updated to iOS4, suffered the decreased performance and want to go back to 3.1.3? Here's how to do it:

What you need
iPhone1,2_3.1.3_7E18_Restore
iPhone1,2_3.1.2_7D11_Restore
redsn0w 0.9.4
blackra1n

Here is how to do it

1. Put your phone in DFU mode

2. Open iTunes hold shift and click Restore at the same time
you will now be able to select the 3.1.3 ipsw

Let iTunes restore your phone after it is finished you will get an error like 1015 in iTunes and your phone will be in restore mode to exit this run blackra1n.

When you get this message click ok and minimize iTunes.
Open blackra1n and click make it 'make it ra1n'.

When you see this:

Physically power cycle the phone at this point the phone will restart normally.

Now run redsn0w 0.9.4 to jailbreak your iphone.

You need to select a 3.1.2 ipsw at this point then follow all the on screen instructions.

When redsn0w has finished and your phone reboots, select Cydia and let it load and update.

When Cydia reboots go to Sources and select repo666 and select ultrasn0w.

When this is installed your phone will reboot and be unlocked!