When building an application and signing with a certificate, signing errors may be encountered stating “The specified item could not be found in the keychain” or “no identity found”. Go to keychain access and make sure that the certificate being used appears under “My Certificates” and has a private key linked. The private key is essentially proof of ownership of the certificate. If the certificate does not appear under “My Certificates”, the private key must be retrieved and imported into the keychain, or a new certificate must be generated.