Jailbreak iPhone 3g on Windows (Firmware 2.2)

Before following this guide make sure you have the latest version of iTunes, if not download it from Apple's website.

These are instructions on how to jailbreak your 3G iPhone to the 2.1-2.2.1 iPhone firmware using QuickPwn for Windows. 

If you are intending to unlock your iPhone you can use this tutorial to jailbreak ONLY if you are on the 02.28 baseband or lower AND you restore to 2.2 (NOT 2.2.1).

Step One
Create a folder called Pwnage on your desktop.

Download the following files and place them in the Pwnage folder you just created:

QuickPwn

FOR THOSE WHO WANT TO UNLOCK: 

http://appldnld.apple.com.edgesuite.net/content.info.apple.com/iPhone/061-5778.20081120.Aqw4R/iPhone1,2_2.2_5G77_Restore.ipsw

FOR THOSE WHO DONT WANT TO UNLOCK:

http://appldnld.apple.com.edgesuite.net/content.info.apple.com/iPhone/061-5828.20090127.aQLi8/iPhone1,2_2.2.1_5H11_Restore.ipsw

1) Extract the QuickPwn-225-2.zip file to the Pwnage folder.

2) Connect your iPhone to the computer and launch iTunes. 

3) Select your iPhone from the list of devices on the left. Now hold down shift and click the Restorebutton. Restore is preferred as it won't create any wasted space on your iPhone

4) Navigate to the Pwnage folder on your desktop and select the firmware ipsw. Click the Open button to continue. 

5) Once iTunes has finished updating your iPhone to the desired firmware you may launch QuickPwn.exe from the Pwnage folder on your desktop.

6) Make sure you iPhone is connected to the computer and click the blue arrow to continue.

7) Click the Browse button to locate your iPhone firmware.

8) Select the firmware ipsw from the Pwnage folder on your desktop then click the Open button.

9) QuickPwn will check to make sure the ipsw is valid. Click the blue arrow button to continue.

10) You can now select whether to Add Cydia, Add Installer, or Replace Boot Logos. Select the ones you would like to perform then click the clue arrow button

11) QuickPwn will now ask you to confirm your iPhone is connected via USB before continuing. Click the blue arrow button to proceed

12) QuickPwn will now automatically put your iPhone into recovery mode. Once its in recovery mode you will be prompted to: Hold the Home button for 5 seconds, Hold the Home and Power buttons for 10 seconds, then release the Power button and continuing holding the Home button until your iPhone is in DFU mode.

13) Watch the prompts carefully and follow along.

14) Once QuickPwn detects your iPhone in DFU mode it will begin the jailbreak process.

15) Once jailbreaking is complete QuickPwn will inform you that it was successfull. 

Thats it, your iPhone is Jailbroken Now. Have Fun