I found out the hard way that this software only works with the "pure" SCP-6600 model Katana. I have Credo Mobile as a carrier and was sent the SCP-6600PL model despite the fact that Credo uses Sprint PCS as their service backbone and Sprint sends out the original model.So if you have a Credo Mobile account, DON'T GET THIS KIT. I'm currently asking Credo which kit will work so I'm afraid I have no suggestions.