How to Tether on an iPhone 3G or 3GS running OS 3.1.2

Here is an updated guide how to tether your iPhone running OS 3.1.2.

At the iPhone OS 3.0 event held earlier this week, Apple execs let it slip that tethering is a feature of the new OS. Apple has done their part, now, it was up to the carriers to enable it on their end. Well, you know, we just couldn’t wait. Here is a detailed guide as to how to enable tethering on an Phone 3G via USB. Bluetooth in 3.0 has some connection issues that I haven’t been able to get around as yet.

Disclaimer: MyAppleGuide is not responsible for any charges incurred as a result of this install. We are also not responsible for any damage to your hardware or software. 

With that said, let’s dive in!

What I’m using: iTunes 8.2, iPhone OS 3.0, MacBook Pro Unibody 15″, connection cable. 

To enable tethering, please have iTunes 8.2 installed along with the iPhone 3.0 OS. 

Before you proceed, open Terminal (Applications>Utilities>Terminal) and type the following:

defaults write com.apple.iTunes carrier-testing -bool TRUE

Step 1

Update your carrier settings. Download this file.  With your iPhone connected, in iTunes, Option+click on “Check for Updates” and update using the downloaded file. (FiIe courtesy of Joachim Bean)

Step 2

On Your iPhone, go to Settings>General>Network and turn on Internet Tethering

Step 3

Quit iTunes, and disconnect and reconnect your iPhone. You will see the following prompt when it is reconnected:

Open Network Preferences and Apply the new settings.

Your iPhone should now have a blue color and displaying tethering at top. If you have any questions, let me know.