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This guide teaches you how to jailbreak your 3G iPhone on the 2.2 firmware using Pwnage Tool 2.2 by the iPhone Dev Team. ONLY WORKS FOR OS X. The 3G iPhone is now unlockable!

This is similar to the 1st generation iPhone method, but is not the same. For the 1st generation iPhone 2.2 jailbreak guide, check here.

Before getting started, you'll need to download a few things:

Pwnage Tool 2.2 - MMi Member Download | Mirror

2.2 iPhone 3G Firmware 5G77 Build Direct from Apple (iPhone 2G Firmware is here)

Note: Safari does not download the .ipsw files correctly - it decompresses them as soon as they're downloaded. We don't want that. Use Firefox to download the .ipsw, not Safari. Or you can ctrl+click the decompressed folder & click the compress button.

Alright, now that you've downloaded all that, lets continue.

Connect your 3G iPhone to iTunes.

I recommend you sync up first so you get your contacts, photos, mail, etc current.

Note: restoring will remove any and all Jailbreak app settings and WinterBoard themes. bhz has a decent guide on how to back all that up here if you'd like. Otherwise, you can just redownload them.

Alright, once you've downloaded the 3G 2.2 firmware and placed it anywhere (I just put mine on my desktop) (or in your Applications folder) you can open Pwnage Tool by double-clicking the icon.

You may have OS X ask you about opening an app from the internet, don't worry about it - click Open.

Hit OK on the Copyright screen that pops up.

Since we're going to be jailbreaking our 3G iPhone, click that image on the left so the green checkbox comes up, and the hit the blue arrow button in the bottom right to move on.

On the next screen, Pwnage Tool will look for the 2.2 .ipsw file. It should find it automatically (again, mine was on my desktop), and list it there. It will take about a minute to find it. Click it and hit the blue arrow in the bottom right to move on.

Note: If you want a larger main partition (for instlaling Cydia apps and themes, etc), click the Expert mode and then the General icon, and increase your parition size.

NOTE - the DevTeam states: ‘Simple Mode’ in PwnageTool currently only works for the iPod Touch. To use PwnageTool for iPhones you will need to use ‘Expert mode’. This is a workaround while we make an update and fix this issue. In order to do this you will need to navigate to the ‘General’ window and change two things: Deselect ‘activate’ ONLY if you are normally able to activate through iTunes (but if you wish to ‘hacktivate’ the iPhone using PwnageTool then leave it selected). You will also need to change the partition size to about 1000MB (type in the value or use the slider).

Pwnage Tool will then let you know its going to create an .ipsw file.

Next, you'll be asked if you have a contract that would activate normally through iTunes - this is AT&T only in the US, or any other carrier outside the US that is a legit iPhone carrier who you bought the iPhone through. IF you have a legit contract with iTunes - say yes.

Once you've answered those q's, Pwnage Tool will begin creating your .ipsw. This screen should be up around 5 minutes or so.

Halfway through the creation of the .ipsw, OS X will ask you for your password. This is required for Pwnage Tool to build the custom firmware, go ahead and input your password and hit OK.

Pwnage Tool will ask if your iPhone has been previously pwned (and still is). If you aren't sure, just hit No, that's fine. If you know for sure its been pwned and still is, hit Yes, but make sure it really is.

Once complete, Pwnage Tool will let you know to quit Pwnage Tool, put your iPhone in Recovery mode (NOT DFU MODE), start iTunes, and restore with the custom firmware bundle it just created.

To put your iPhone in Recovery mode, make sure iTunes is up and the iPhone is connected via the USB cable. Then, simply hold down the Home and Sleep buttons on your iPhone for about 25 seconds (even after the boot screen comes up) until you see the little Russian Steve Jobs character you get after pwning your device (i.e., the connect to iTunes replacement screen).

Now, pull up iTunes. You should see the following message:

Hit OK. Now, this is important - where it says Restore in iTunes, hold down the option key on your keyboard and press Restore in iTunes while holding it down.

Note: Its very important you hold down the option key while pressing Restore. Don't forget that.

Assuming you did that correctly, a window should pop up asking you which .ipsw file you'd like to restore from. Select the one we just created with Pwnage Tool. If you left it default, it should be sitting on your desktop and be named iPhone1,2_2.2_5G77_Custom_Restore.ipsw or something similar. Hit Open.

iTunes will now run through its typical flurry of windows and notifications while updating the firmware.

During this time, you'll see the nifty new progress bar on your iPhone as it restores.

If everything went correctly, you'll see the window stating your iPhone was restored to factory settings (heh, not quite, iTunes ;), and you can then hit OK.

Wait for iTunes to see the iPhone before disconnecting.

If you'd like, you can now restore from the backup you made of your iPhone before, to get all your contacts, mail accounts, and photos back. You might wanna clear off some photos/videos/music if you had it near full to make room for AppStore and Cydia apps now.

Congrats! That's it! You're now ready to go on iPhone firmware 2.2.