I want to reset my iPhone, but don't know the restriction passcode?

My iPhone was stolen recently, and so my friend gave me their old iPhone. I want to reset it to factory settings to get rid of all their stuff, then sync it to my iTunes to put my stuff on it. However they have a restriction passcode on the reset option, and they can't remember it. How can I reset my phone without knowing the password?

Hook your iPhone into the computer (while your phones on) Hold both the power, and home button until it turn off, and keep holding them until the apple logo appears, than release the power button but keep holding the home button. It should put it in recovery mode and let you restore it.

The other guy is right, but here's an easier way.

1. Turn off the iPhone

2. Hold the home button while plugging your iPhone into the computer

3. After some time the iPhone should display a picture of a USB Plug and something else

4. The iPhone is now in recovery mode

5. Now in iTunes it should say something about the iPhone is in recovery mode and you HAVE to restore it

6. That isn't entirely true about HAVING to restore it but since you want to restore it, hit the restore button. Now the phone should be restored and you can do the stuff which you wanted to do