This guide is just a workaround as there is no official iPhone 3GS 3.1 jailbreak tool for Windows yet. We are going to get a custom firmware cooked on a Mac machine and install it on your iPhone 3GS on a PC. This is a safe and simple way to update your iPhone 3GS to a custom jailbroken 3.1 firmware.
Please read the following paragraph very carefully before doing anything.
If your iPhone 3GS has 3.1 preinstalled and is not pwned then there is no tested jailbreak solution at the moment. In other words, if you are on a pwned version of 3.0 or 3.0.1 (either using PwnageTool, RedSn0w, or PurpleRa1n), then you are fine; just follow this tutorial. If you updated to 3.1, or if you bought your iPhone with 3.1 already installed, you will have to wait for another method. We don’t know when this other method will be available.
1. Some basic requirements
- You need to update iTunes to the latest version available
- You need to sync your iPhone in order to back it up
- Tricky part: you need to find a custom IPSW file. Don’t ask for it here. For legal reasons, we can’t post it but a little bit of digging around on Google will help. Search for terms similar to: “custom iPhone 3GS 3.1 firmware” or “iPhone2,1_3.1_7C144_Custom_Restore”. Download the file once you find it and save it to your desktop.
- Or even better, if you have a friend who has a Mac, simply use it to create your custom firmware by following this tutorial
2. If you just updated iTunes or if you just synced your iPhone, I suggest your reboot your PC. Just to be safe, reboot your iPhone as well.
3. Launch iTunes and plug your iPhone. iTunes will recognize your iPhone and will ask if you want to install the new 3.1 firmware. Say NO.
4. Now we are going to restore your iPhone using the custom IPSW firmware you downloaded in step 1. To do so, hold the “SHIFT” key on your keyboard and click on “RESTORE” in iTunes. Make sure you hold the SHIFT key while you click on RESTORE, or else, it will restore your iPhone to the official 3.1 firmware.
5. A window will pop up, allowing you to browse for the custom firmware we downloaded in Step 1. Look for it and select it.
6. You iPhone will now be restored using the custom IPSW. This is going to take a few minutes so don’t panic.
7. Once done restoring, your iPhone will reboot and you will have a clean jailbroken iPhone 3GS running OS 3.1.