UPDATE : A new version of custom firmware 3.1 for iPhone 2G/3G/3GS is now available here!

Free your iPhone 3G 3.0 from Apple’s chain by jailbreaking your iPhone which provides you with various customization features and even unlock feature which Apple and your official carrier hate! There are various options available to achieve this level of customization on your iPhone such as download firmware files, bootloader files, jailbreak/unlock tools such as Redsn0w/Pwnage or QuickPwn.

If you are not the one to download all the various files and just want the ultimate result, these files are waiting for you to download! If you rather want to start from scratch, this guide is for you.

• Caution #1 : Please proceed further only if you have an iPhone 3G. For all other devices, there is an other post in the works.
• Caution #2 : Ultrasn0w (iPhone unlock s/w) is yet to be released (soon). If you are looking for iPhone 3G unlock, please hold off for a day or two. Proceed only if you have no carrier signal at the moment and want to activate and jailbreak your iPhone 3G. You may also proceed if you signed an official iPhone contract and need jalbreak stuff! Ultrasn0w is now released!
• Caution #3 : A restore is going to wipe the iPhone clean. Hence, please make a backup of all the info using iTunes and then proceed.

Step 1) Download Files (Please read the following carefully)

• Download the following files ONLY if you have an Official iPhone contract with your cell carrier (ATT and others….)

iPhone 3G 3.0 Custom Firmware Not Activated Official Carriers Part 1

iPhone 3G 3.0 Custom Firmware Not Activated Official Carriers Part 2

OR

• Download the following files ONLY if you don’t have iPhone contract (T-Mobile and others…)

iPhone 3G 3.0 Custom Firmware Activated for Other Carriers Part 1

iPhone 3G 3.0 Custom Firmware Activated for Other Carriers Part 2

Step 2) Join the downloaded files

• The files downloaded above have an extension .001 and .002. They need a special opensource (free) software HJSplit to join.

Download HJSplit to join both the files – Link for Windows Computers here and Macs here.

Step 3) Restore the firmware in iTunes  8.2

• You should now have the respective firmware file with an extension .ipsw . Please follow the steps in order.

Launch iTunes and connect the iPhone to your Mac / Windows computer.

If you are aware of DFU mode, proceed further. If not, watch this quick video and pay close attention to the steps to achieve DFU mode.

Turn your iPhone off. Press and hold the Home button and the Power button at the same time for 10 seconds.

After exactly 10 seconds release the Power button. Continue holding the Home button until iTunes pops up a message saying that it has detected an iPhone in recovery mode.

The iPhone will show you a blank screen (black).

Click on ‘Ok’ to the prompt displayed and hold Option key on your Mac and then hit Restore button. For Windows, hold the shift key and then hit the restore button. In the dialog box that pops up, browse the downloaded custom firmware file.

Step 4)  Give it few minutes to perform the restore. Once the iPhone is up and running, proceed for software Unlock using Cydia. Follow this guide to install Ultrasn0w to software unlock your iPhone 3G.

You are now good to go! Please post a comment if you are stuck at any of the steps described above.

Related posts:

1. Download Custom Firmware 3.1.3 IPSW – Jailbreak, Activate, Unlock iPhone 2G, 3G, 3GS [Mac + Windows]
2. Download Custom Firmware 3.1.2 IPSW – Jailbreak, Activate, Unlock iPhone 2G, 3G, 3GS [Mac and Windows]
3. Download Custom Firmware ipsw files for iPhone 2G, 3G 3.1 [Windows/Mac] , Error 1600 Solution Updated
4. Redsn0w is the new QuickPwn – Activate,Jailbreak,Unlock iPhone 2G, iPhone 3G / 3GS, iPod Touch Firmware 3.0 [Windows and Mac]
5. Download Custom Firmware to Jailbreak and Unlock iPhone 3GS 3.1 [Mac/Windows]