How to unlock my iPhone 4 (Version 6.0/ AT&T)?

How do I unlock my iPhone 4 (Version 6.0/ AT&T) ? Help?

Added (1). That article is 5 years old.
Does anyone have something up to date?

Well you should go to a store or go to this http://www.pcworld.com/...ticle.html

Only att can unlock that.call and see or fill out a unlock request online.

To Unlock I-phone 4 use Remote Unlock service… Visit the site http://www.simpleunlocking.com/apple-iphone-4/rs16wp9/ get the remote Unlock service and Unlock it from AT&T Network lock USA… Then use with other GSM Network Sim card in it. You can follow the unlocking instructions below and unlock it step by step… This is Latest Unlocking and best Unlocking Method.

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Apple iPhone 4 Unlocking Instructions:
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1. Wait for us to send you an email saying your phone has been activated or remotely unlocked.
2. Install the latest version of iTunes.
3. Make sure your Apple iPhone 4 phone software is updated to the latest version using the iTunes software.
4. Connect your Apple iPhone 4 to iTunes with a NOT ACCEPTED SIM card.
5. Wait until iTunes detects your Apple iPhone 4.
6. Disconnect your Apple iPhone 4 and reconnect it after 10 seconds.
7. Your Apple iPhone 4 is now unlocked.

You can surely done it here
http://www.vunlock.com/
they are att experts

Go to http://attiphoneunlocker.com/ Cost $24.95 Once you receive your email to confirm that your handset is unlocked, for the iPhone Connect to itunes with a non accepted sim (for example a tmobile sim) and do a back up and restore. Your phone can now be used with any gsm network.

Instructions - to unlock iPhone Please Download latest version of Itunes from Apple Website. 1. Once you do this please Connect the Phone via the usb cable while Itunes is on. If your phone is not the current version (most updated), it will prompt you to update. Please update to current version (which is most likely 5.1.1) 2. Please insert foreign sim card (Please make sure the sim card is cut to fit in the slot) 3.It should automatically detect the new network. If it does not please go to Settings > General > Reset > Reset Network settings. It will take about 30 seconds. It will not show on Itunes that the phone is unlocked. You will see the phone Searching for signal. If it does not please do a Restore and restart the phone. 4.It should now be unlocked permanently!

There's a possibility the code will be returned as NOT FOUND and its not in our control. If that happens you will be refunded.
http://attiphoneunlocker.com/