This guide is for Windows users only.
Mac users should follow the guide here.
The following edited text is taken from:
How to Jailbreak And Unlock Your iPhone With Blackra1n And BlackSn0w on Windows
We had recently written about the release of Geohot’s iPhone jailbreaking tool Blackra1n.
Here is a short tutorial that you might find useful in using these tools to jailbreak and unlock your iPhone 3G or iPhone 3GS on your Windows PC.
Some important points to note before we start:
Hacking your iPhone could void its warranty. So please proceed with caution and at your own risk.
Make sure that you have iPhone OS 3.1.2 installed on your iPhone.
The jailbreak requires 05.11.07 baseband .
Please take a backup of your iPhone, refer to this post for more details.
After you have successfully jailbroken your iPhone, please checkout our article on tips to keep your iPhone secure.
Instructions to Jailbreak
Step 1: Visit Blackra1n website and choose the software for Windows by clicking on the Windows logo
Step 2: Download the software.
Step 3: Connect your iPhone or iPod to the computer and run the downloaded blackra1n executable file
Step 4: You will now be shown a button that reads ‘Make it ra1n’. Click on the button to the jailbreak process
Step 5: Notice the following events on your iPhone:
The iPhone is placed in recovery mode.
The recovery mode is replaced by a picture of Geohot on your iPhone or iPod.
Your device will reboot.
Step 6: You are shown a pop-up. You may press OK
Jailbreaking is complete. You can now see the blackra1n icon on your springboard. If you want to proceed to unlock your iPhone, follow these steps below.
Instructions to Unlock your iPhone:
Step 1 Make sure you are connected to the Internet and click on the blackra1n icon.
Step 2 Select sn0w and tap on Install to start the unlock process.
Step 3 Once the installation is complete, you are shown a confirmation screen. Tap on ‘Close’
Step 4 Unlocking is complete. You can confirm this from the Blacksn0w icon on the springboard.
Step 5 You may uninstall blackra1n now. Tap on the blackra1n icon on the springboard and press uninstall.
That’s it folks. Your jailbreaking and unlocking is complete. We have all along been fans of Geohot and if you are impressed with his software, take a moment to make a donation by visiting his website.