If you used to be a proud owner of a working and fully unlocked iPhone 4 then this post might be for you; if your iPhone 4 has been upgraded to iOS 5 without preserving the baseband then this post is definitely for you. As you may already know, it was said that unlocking the iPhone 4 on iOS 5 using baseband 04.11.08 would be impossible or not possible for the foreseeable future. this put a lot of us in a downward spiral of sadness and shame because this meant our beloved phones would only be able to function merely as an iPod touch.
Recent discoveries have brought some light back to this topic, but this time with some positive news. It is now possible to unlock your iPhone 4 on iOS 5 without even having to jailbreak it or purchasing a Gevey SIM.
The process is a little tricky and has thus far worked for a few people, give it a go and let us know if it worked for you too.
Step 1: Get the original SIM card for the phone, i.e if its an AT&T phone get the AT&T sim card. I used a sunrise SIM card if it matters.
Step 2: Turn on the phone with the original SIM, when its on disable WIFI immediately, now dial the customer care line, in my case it was 0800 707 707 or I don’t know it this would work but also try dialing 112.
Step 3: cancel the call and enable airplane mode, once you have done this you should remove the SIM and replace it with the SIM you wish to use the phone with (i.e. the locked SIM).
Step 4: now disable airplane mode, the phone will freeze and show you the boot screen, apple splash screen, followed by activation screen.
Step 5: wait until you see the “E” (edge) sign on the top left of the screen, once it appears wait 15 seconds then turn the phone off, then on again. You will see the activation screen once again.
Step 6: wait for a signal to appear on the top left side then select use cellular connection.
Step 7: Remove your SIM, wait for a prompt on the screen, then re-insert your SIM.
The iPhone 4 should now be unlocked!