...your SIM card might not be activated. Usually whenever it says "unregistered SIM" (or something similar to that), your SIM card does not have service. Either that be the case, or that you actually do have an account with your service provider, that should be brought up to them. Because if you do have an account with them, that would be the direction to deal with and have things sorted out. We cannot help you entirely but suggest what to do...and like I said in your other thread, contact your service provider which is 3.
Dude, like what X-factor said, also check to see if this phone is carrier unlocked. Last I remember, I think this phone is locked to Vodafone (or was it the 6681, I dont remember...if I'm wrong someone here will correct me).
