Smartphone Questions? Ask A Smartphone Technician for Answers
Welcome to JustAnswer.Did you lock it from the "Find My iPhone" app? If so, you will need to use that passcode that was entering from the app to lock it.If that does not work, or you do not remember the passcode, the only option will be to wipe the device and start over from scratch. There are no other options.How to Perform a DFU Restore (which is significantly different from a standard restore):First, with your iPhone is plugged in to your computer, hold the Home and Power until your iPhone powers down, continue holding Home and Power for a full 4 seconds.If you are having trouble with this, please refer to the video below for assistance.http://www.youtube.com/watch?v=ofpinyGlQ8IRelease the Power while still holding the Home key until iTunes tells you the iPhone is in recovery (your iPhone screen will be black, but it is on) and then doing the restore to latest firmware.After the restore, when prompted, select Setup New iPhone (not Backup From Restore). From there, you will need to resync any apps, music, and videos to your iPhone from iTunes.Let me know if you need further assistance.