I bought the more used and called att and asked to check the imei number so I could know if I would be able to activate it on a new account. She said sure let me get the unlock code. She then told me to put a non att Sim in and when prompted pig in the unlock code. She have me the unlock code no pro Ken and it worked great. I used a t mobile Sim .I tried net 10 Sim first and it wouldn't recognize it.