UltraSn0w 1.2 is finally out and you can currently use it to unlock the iPhone 3G / 3GS on iOS 4.2.1. This guide will help guide you in the process of unlocking the iPhone 3G / 3GS on iOS 4.2.1 with baseband 06.15.00 with ultrasn0w. The instructions can be found below:

IMPORTANT:

• Your iPhone 3GS or iPhone 3G must already be jailbroken.
• For baseband 05.14 or 05.15 your need to update your baseband to 06.15.00. A step by step guide has been posted here.
• This UltraSn0w update can unlock baseband 05.13.04 or older too.

NOTE:

This is NOT for iPhone 4 users. iPhone 4 unlock will take some more time.

Disclaimer:

This guide is for information and educational purposes only. Use it at your own risk, we cannot be held responsible if anything goes wrong.

How to Unlock iPhone 3GS/3G with UltraSn0w

Note: T-Mobile USA users please disable your 3G network first. (You can do so by going to Settings > General > Network and turn the “Enable 3G” switch to OFF)

Assuming that your iPhone 3GS/3G is already jailbroken on iOS 4.2.1/4.1

Step 1:

Open the Cydia.

Step 2:

Go to Manage Tab at bottom.

Step 3:

Hit the big Sources button.

Step 4:

Hit the Edit button on Top-Right

Step 5:

Then Hit the Add button on Top-Left

Step 6:

Then Enter the following URL: https://repo666.ultrasn0w.com and hit the Add Source button.

Step 7:

Once the Source is added to the Cydia, hit the big Return to Cydia button at bottom of the screen and then Done button.

Step 8:

Go to Search tab and search for ultrasn0w and install it.

By installing ultrasn0w you will unlock your iPhone 3GS or iPhone 3G on iOS 4.2.1 with baseband 06.15.00. Once the installation is complete, just reboot your iPhone and you are done! You have successfully unlocked iOS 4.2.1 on iPhone 3G / 3GS baseband 06.15.00 with Ultrasn0w and can use a SIM from any carrier now.

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Authors: TechHead

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