Small issue I just ran into working on a group XCode project - I was greeted by the message "Code Sign error: The identity 'iPhone Developer' doesn't match any valid certificate/private key pair in the default keychain". Simple fix, by going to > Project settings/ overview > Targets (select the target file) > Under Code Signing make sure your developer certificate is selected and not that of the project author that may have overwritten yours as in our case using GIT.