Solved:
UPDATE EDIT: This method will work to unlock and jailbreak, BUT will potentially affect your iPhone detrimentally in a few ways:
1. Jailbreaking invalidates your warrantee.
2. You will lose GPS if you change to iPad baseband.
3. Once you have changed to iPad baseband, it is CURRENTLY supposedly impossible to downgrade. (The Dev Team are working on this...)
3. You may not be able to update using official firmware from Apple in the future.
HOWEVER: This tutorial is for the 3GS, which is now a relatively dated model, very soon to become even more outdated. I made these changes on my phone as I intend to get the iPhone 5/ 4S when it is released anyway - these were acceptable risks. Update according to your own situation.
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Ok, guys, despite a lack of response, after about 10 hours of rigorous googling I have successfully unlocked my iPhone.
For all those who are interested, these two resources were essential:
-
http://jailbreakqa.com/questions/57088/how-to-unlock-435-on-51602
-
http://www.youtube.com/watch?v=m4H2tUcz890
The YouTube video helped me specifically because I was unable to log in to Cydia to download UltraSn0w as I had no WiFi connection on my iPhone.
You will need:
- TinyUmbrella (whatever the latest version is)
- RedSn0w 0.9.6rc18 (NOT the latest version...) here on Mac:
https://sites.google.com/a/iphone-dev.com/files/home/redsn0w_mac_0.9.6rc18.zip?attredirects=0&d=1 and here on Windows:
https://sites.google.com/a/iphone-dev.com/files/home/redsn0w_win_0.9.6rc18.zip?attredirects=0&d=1 (IMPORTANT: if you are doing this on Windows you will need to be in Windows XP Compatibility Mode.)
- iTunes (the latest version)
- 4.1 Official Apple Firmware from here:
http://appldnld.apple.com/iPhone4/061-7938.20100908.F3rCk/iPhone2,1_4.1_8B117_Restore.ipsw
You may need:
- DiskAid (if you have no WiFi like me)
Follow these steps:
1. Run TinyUmbrella and go to the Advanced Tab.
2. Make sure "Set hosts to Cydia on exit" is UNCHECKED.
3. Exit TinyUmbrella.
4. Open iTunes.
5. Put your phone in DFU recovery mode (Hold 'Power Off' and the 'Home' button simultaneously for 10 seconds, then let go of 'Power Off' but continue to hold 'Home' for another 20 seconds)
7. iTunes should recognise an iPhone in recovery mode.
6. Hold 'alt/option' and click Restore.
7. Choose to restore from the 4.1 IPSW file referred to above.
8. iTunes will act like it is restoring and then at the last minute encounter error 1015. This is exactly what we want.
9. Open TinyUmbrella again.
10. Click 'Exit Recovery'.
At this point, your iPhone now runs on 4.1 Firmware. Progress!
11. Open RedSn0w and click Browse.
12. Select the same IPSW as previously (4.1). Click next.
13. Choose to Install Cydia. DON'T opt to change baseband yet or it might crash!
14. Click next. Go back in to DFU mode as described above. The RedSn0w page will automatically begin to update and inform you that it is installing. Your iPhone will display: "Downloading Jailbreak Data..."
15. When this is done (your phone will eventually reboot), exit RedSn0w and turn your phone back off.
16. Now open RedSn0w again. Click Browse.
17. Choose 4.1 IPSW again. Click next.
18. This time deselect Install Cydia and instead check the box to install iPad Baseband. IMPORTANT NOTE: you may lose GPS connectivity in your phone if you do this, but it is an essential step to unlocking your phone. Bite the bullet.
19. Click next and return to DFU mode as before. RedSn0w will now show another little Pineapple image and begin installation of iPad Baseband.
20. Your phone should restart and your good to quit RedSn0w.
At this point, your firmware is version 4.1 and your BB is 6.15.00! Now you just need a final step.
21. If you can connect to WiFi, open Cydia. If you can't, watch the YouTube video I linked above.
22. Once in Cydia, select the Manage tab (along the bottom).
23. Click Sources. Click Edit, then in the top left, Add.
24. Type:
http://repo666.ultrasn0w.com/
25. Click ok. Then in the top right click Install.
It will install UltraSn0w and should provide you with a message which confirms it is able to unlock your BB (6.15.00)
26. Restart your iPhone. (Do it twice to be on the safe side.)
27. Put in your new SIM from your new carrier.
28. Go to Settings and turn Airplane Mode off and on again.
29. It will say 'Searching...' for a little while and then:
30. SIM/ NETWORK ACTIVATED!
I hope this guide has helped you. It was such a time consuming nightmare for me that I wanted to make sure it wouldn't be such a trial for everyone else. GOOD LUCK!
ps. Yes, I'm afraid that means the offer of money is officially retracted
pps. If in doubt, DFU mode and restore to 4.1 again and restart the process.