HOW DO I UNLOCCK MY IPHONE WITH A SIM PIN

You must have received a metal PIN in Box of Iphone 4s. Just with the help of that PIN you can open the SIM Slot and insert the Mini SIM.
Hope it helps

No Sim Card Installed Insert a valid Sim with no pin lock

Don't worry, you can still get the sim cardout. Here is a response with pictures that explains how to do it without theremoval pin tool http://www.wikihow.com/Get-a-SIM-Card-out-of-an-iPhone

Theremoval tool for iPhone Sim cards looks like this
Hope that helps!

I assume that your iphone is not locked to any cell phone company ...

Insert your SIM in your old phone/another phone and remove the SIM pin lock/password, then try this unprotected SIM again in your iphone. Once it is accepted in the iphone, put the SIM lock/password back using the iphone.
Hope it helps.

your iphone comes with a pin that you can use to remove the sim. the sim tray is on top of the phone (between the hold/power button and the headphone jack) there is a hole there. insert the pin to push the sim tray out.

Try replacing you sim and if you still get the same error then it is a device issue. You will need to contact your service provider for replacement options!

look at the top of the phone , there is a small pin hole, take a pin and poke in it. and the SIM card holder tray with SIM in it will eject out. the tiny oval plastic piece will come out and its has a little disc made for sim put sim in, and pop back into iphone 3g.hope this helps

Take the SIM out of the phone and carefully rub the sim contacts with a pencil eraser. Do the same with the contacts in the phone and try again.

what sim card are you trying to use after the restore in itunes and also when you finished the restore in itunes did your iphone come up with a message saying iphone activated?

go here click here and tell him what has happend this chap is a god with iphones he actually makes his own software etc for iphones.