Iphone 4 Unlock? No sim or passcode?

Okay so i have an iphone from my friend and it doesn't have a sim card and the phone has a passcode. I do not know the passcode and i can't get into it at all. I tried connecting to itunes and it wouldnt show up on the let side of the itunes bar where it should. I was wondering how i could get into the phone

The only way to use the phone at that point is to completely reset it. If you can't do it on your computer, bring it to an apple store and they might be able to. They will most likely want some sort of proof you bought it as well.

Make sure your computer is showing something connected to it. If not try another usb port, but it should show in iTunes and give you the option to wipe it.