As you are aware, George Hotz (aka Geohot) had released a software called purplera1n to jailbreak iPhone 3GS.

This allows the users to jailbreak their iPhone 3GS running iPhone OS 3.0. Here is our step-by-step guide to jailbreak your iPhone 3GS using purplera1n for Windows users.

Before we start some important points: 

• Purplera1n is currently available only for Windows users.
• This one is only for iPhone 3GS users, if you are an iPhone 3G users, please checkout our step-by-step guide to jailbreak iPhone 3G running iPhone OS 3.0 for Windows or this one for Mac users.
• Jailbreak apps like WinterBoard, VOiPOver3G etc don't
  seem to be working on iPhone 3GS, so you might have to wait for the
  developers to release updated version of the jailbreak apps.
• This guide only shows you how to jailbreak iPhone 3GS, it does not unlock it.
• As with any hack, please proceed with caution as jailbreaking your iPhone could void it's warranty.

Step 1: Download  purplera1n from  http://www.purplera1n.com. Please ensure you have downloaded the latest version. It is currently RC2 in which Geohot has fixed quite a few issues.

Step 2: Once the exe is saved on your desktop, double click on it. Click on the make it ra1n button.

Step 3: This will put your iPhone in to recovery mode. A picture of GeoHot will replace the recovery mode screen on your device.

purplera1n will run, which will reboot your device.

 

Step 4: After your device reboots, you will be able to see a new app icon on the SpringBoard named Freeze. Click on it to launch

Step 5: This will open up Freeze, now click on the Install Cydia button at the bottom.

Step 6: The cydia installation process will download cydia and once the status changes to Finished!, you must reboot your iPhone.

 

Step 7: After you have rebooted your iPhone, launch Cydia and let it run all the necessary updates.

Update:

Please note that this guide only jailbreaks iPhone 3G running iPhone OS 3.0, you will need to install UltraSn0w via Cydia to unlock iPhone 3GS. You can checkout our step-by-step guide to unlock iPhone 3GS using UltraSn0w.

As always, please let us know your thoughts in our comments section below.

[via iClarified]