My wife lost one of the 2 smart keys that came with our 2006 Prius and I want to get it replaced without spending a small fortune. I bought one from a seller on e-Bay but a local Toyota dealer couldn't program the smart key to my Prius. The e-bay seller exchanged it for another one and this time I went to a different dealer, but they couldn't do it either. That dealer told me that the only way I could get any smart key programmed was if the remote had NEVER been programmed before. Does anyone know whether or not a used smart key can be reprogrammed or do I need to buy a brand new one? Thank you very much for your assistance.