I need some advice on how to respond to this situation. I sold my old unlocked iPhone which I also had originally bought from someone on craigslist. Met up with the dude about 4 months ago to sell him the iPhone which I had advertised on criagslist as UNLOCKED. He wrote me an angry email 4 months later (today) saying that AT&T is charging him $800 because the iPhone is not registered under his name. He threatened me in the email stating that I 'cheated' him and his uncle works for the police and he will come find me. I find this situation kind of comical. NO, I am not trying to scam some guy. I simply posted the iPhone on craigslist as a "8gb Unlocked iPhone" which he purchased from me in person. I mean am I responsible for these charges he is getting from AT&T? I have never heard of AT&T applying charges for iPhone registration? When I bought the iPhone all I had to do was pop my T-Mobile sim card in it. What I dont understand is why he is emailing me with threats 4 months after I sold him the iPhone. ***UPDATE**** I emailed him back stating that the iPhone he bought from me was an UNLOCKED iPhone which I used for T-MOBILE. I asked why he was emailing 4 months later. He responded by saying he wants me to call him asap so we can have a conference call with AT&T. He wants me to tell AT&T that the iPhone is registered under my account so they can drop the charges. (WHY THIS GUY THINKS I HAVE AN AT&T ACCOUNT AFTER I TOLD HIM REPEATEDLY I USE TMOBILE IS OUT OF MY MIND) He said if this goes on any longer more charges will occur. I really do not want to waste my time with this guy. The person I bought the iPhone from (Almost 8 months ago) may have activated the phone through AT&T and then unlocked it. I dont have the contact info from that dude though. This guy just needs to re sell the phone to someone who will take advantage of it being unlocked. I forgot to mention earlier that when we met up (at starbucks) after we had made the transaction he sat in his car for a little while then ran out to where me and my friend were sitting and took a picture of me with the iphone. His rude email also stated that all he needed was my photo and that he would find me. How creepy.