How to Unlock an iPhone 8Gb

Unlocking your iPhone is a method of removing the SIM lock so it can be used on a GSM cellular carrier besides AT&T to make and receive calls. Armed with a bit of know-how and Internet saavy, you'll be unlocked and making calls in no time.
For this article we will use QuickPWN, a free program that also gives you the option of jailbreaking your iPhone. Many unlocking methods exist, but this is by far the easiest and most reliable.

Difficulty: Moderately Challenging

Instructions

Things You'll Need:

• iPhone
• iPhone USB cable or dock
• computer
• unlocking software
• SIM card
• SIM card removal tool

1. Backup and restore your iPhone through iTunes.
   With your iPhone connected to the computer, open iTunes and click on your iPhone in the left-hand window pane. If your iPhone does not sync automatically, click "Sync" in the "Summary" tab to make a current backup.
   Now that it is backed up, click "Restore" to wipe your iPhone clean and restore factory settings. While this step may not be necessary, it will prevent any installed applications or changed settings to interfere with the unlocking process.

2. Note the firmware version.
   Once your iPhone is restored (this can take a long time, be patient), check your phone's firmware version by browsing to Settings>General>About>Version. Write down this number.

3. Insert SIM card into the iPhone.
   The SIM (Subscriber Identity Module) card stores unique data about your account to identify your device on the mobile network. Once you have the SIM removed from your old phone, pop out the iPhone's spring-loaded SIM tray. Use the supplied tool or a bent paperclip to depress the button, located at the top of the phone in a recessed hole. Insert the SIM carefully into the tray (it only fits one way) and slide it back into the iPhone. An error message will pop up, ignore it.
   Although you can unlock your iPhone without a SIM, it is recommended that the SIM stay in the entire unlocking process to prevent compatibility issues with your carrier.

4. Download and install three things: QuickPWN, firmware and boot loaders.
   Browse to QuickPWN's home page and find the download section. Once there, download QuickPWN and the matching firmware version (from Step 2).
   Use the link supplied to download the bootloaders.
   Once you have these three things extracted and saved to a folder on your computer, you are ready to start the unlocking process.

5. Unlock your iPhone.
   Run QuickPWN and follow the onscreen instructions. It will ask you to select your iPhone version and instruct you to locate the firmware and bootloaders. Be prepared to press a series of buttons in succession. If you mess up, don't worry, you can try again once the sequence is complete.

6. Finish the process.
   Once QuickPWN has finished its magic, your phone will be unlocked and ready to make calls on your new carrier.

Tips & Warnings

• Check with your cellular carrier before unlocking to ensure your iPhone will work on its network. It should work with most GSM carriers in the US. If something goes wrong during the unlocking process, restore your iPhone through iTunes and run QuickPWN again.
• Remember you are unlocking your iPhone at your own risk and success is not guaranteed. Conduct your own research before attempting to unlock or otherwise modify your iPhone. Apple will not service an unlocked iPhone. Once your iPhone is unlocked, DO NOT allow iTunes to update it. Syncing is safe, but updating the firmware will re-lock your iPhone. If you want to update the firmware, run QuickPWN again with your desired firmware version.