Try to put it into DFU mode.
Start iTunes and connect the iPhone.
Hold the power and the home button down.
After 10 seconds release the power button but keep the home button held down.
After a another 10 seconds or so the iPhone should go into recovery mode and iTunes will say it has detected it and it needs to be restored before you continue.
Follow the on screen prompts from there.
If that does not work then you need to look for a new phone.
You can call Apple at 1-800-myiPhone but they will tell you the same thing more than likely