Hack the iPhone

Downgrade and/or repair the baseband

(Windows XP / Vista)

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The only reason I can think of to downgrade the baseband would be to fix a corrupted IMEI. In this case the IMEI would change to 004999010640000.

Repairing the baseband (which can be performed independently from downgrading), is only done when you used anySIM prior to version 1.1, or iUnlock or the hardware unlock method to unlock your iPhone. When you repair the baseband you must be on 1.0.2 firmware. This is done just before updating to the newer firmware that you want.

The process of downgrading and repairing has become much easier now that all the necessary tools have been compiled into self-contained applications. The downgrading programs I offer on my Installer repository are:

• Downgrading firmware 1.1.2 (04.02.13_G) baseband to firmware 1.0.2 (03.14.08_G) baseband.
• Downgrading firmware 1.1.1 (04.01.13_G) baseband to firmware 1.0.2 (03.14.08_G) baseband.

Make sure you are downloading the correct one. It's not a good idea to have both programs installed at the same time as they will conflict with each other since they both use a binary with the same name!

Step 1. (downgrading)

First you need to downgrade your firmware to 1.0.2 using iTunes. If you don't already have the firmware, you can download it here. Do not decompress this file, or allow your browser to decompress it. Save it wherever you'd like.

Step 2.

In my case the iPhone is not activated yet, so I have to put it into DFU mode. If yours is activated already you don't have to do this.

Restore the iPhone to 1.0.2 firmware by putting the iPhone into DFU mode. Do this by pressing and holding the Home button, and the Sleep/Wake button.




Hold the buttons 10 seconds and the screen will go black. Let go of the Sleep/Wake button. Continue holding the Home button for another 10 seconds and iTunes will detect that the iPhone is in recovery mode.




Press Shift then click the Restore button.




A file browser will open. Navigate to where you downloaded your 1.0.2 firmware file. Select it and click Open.




Various messages will appear while the process continues.




You will then get an error 1013 message. Click OK. The recovery mode graphic will appear again, click OK.




Eject the iPhone from iTunes and close iTunes.

Step 3.

Launch iBrickr v0.91. If you don't have it you can download it here. Once you start it you should see this screen. Click the Boot the phone link.




The iPhone screen should turn red while displaying this graphic.




Next this activate iPhone screen should appear.




Close iBrickr.

Step 4.

Download AppTapp Installer here. Double click the installer icon to get started.




Click "Continue".




Select the firmware version on your iPhone and click "Install".




A status bar and several messages will go by.




A command shell will open and the install process will display.




This is the last screen you'll see for the installer. The status bar never completed but it said it complete. Just click "Close". The Installer program is now installed.

Step 5.

Download iDemocracy here. Keep in mind there is an update for it you may want to install right away. Launch the program and click the Jailbreak + Extras button.




Click the Non AT&T Tools tab and click the Activate 1.0.2 button.




Code will scroll by in a DOS window. When it finishes just press any key.




The activation pop up will appear, click OK. The iPhone should now give you access to the SpringBoard.