Man I just got a 40 minute call here at this tech support job (the elder didnt know computers well). Got a error 550 Invalid recipient. We deleted and recreated the account and checked the properties twice. We checked the email address that he is sending and it is right. I think it might be for some reason trying to send out of the address book and may be a corruputed address book issue. I called around here at work and no one knows. Transfered to a higher level tech and they didnt know. What is this weird error?