Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_2_6 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8E200 Safari/6533.18.5) Hi there, I'm looking into selling my Verizon iPhone 4 16gb. I know that you should stay away from buying a phone with a "bad esn". Here are my questions: 1. What is an esn and what makes it bad? 2. When I sell my iPhone, how can I make sure it doesn't have a bad esn and that it will work for the person who buys it? 3. Is there a way to "clean" a bad esn? Thanks so much!