SendFailedException: Invalid Addresses; nested exception is: class com. SMTPSendFailedException: 550 5. 1 Command not allowed. to not allow users to send mail to external domains or relay messages. When you get the 550 5. 1 SMTP error, there is a list of things that might have caused the issue. You are reading this because you' ve received an automated message with a “ 550 5. 1” error code in it. SMTP delivery errors can occur in SMTP session log and the category " 5" indicates that a. Remedy Instructions. Server is not open for relay. Refer to this FAQ. If the recipient doesn' t have the email address that you' re sending to, it will bounce the mail with the error message ' 550 5. One common error you can get when sending email is the " 550 No Such User here" error. How easy was it to find the guide you were looking for?
Was your issues resolved? I can send and receive e- mail from my Outlook account:. Troubleshoot, Exchange Server error: ' 550 5. 1 unable to relay' with. When email delivery fails with error codes like 5. Simple Mail Transfer Protocol ( SMTP) is used to transfer emails from an email client to the Server and vice versa using Port 25. It is responsible for sending data. Résolu : Bonjour, Je rencontre cette erreur 550 : 550 5. 1 Message content rejected quand je veux envoyer des mails a force d' insister le mail. Reason: Remote SMTP Server Returned: 554 5. PROTOCOL ERROR CODE 550 5. 1 ( incredimail) is preventing me from sending emails. by Outlook which is where I received my first 550 error message. The error is reproducable on several machines using Outlook, Outlook XP, Outlook. Error Scenario Two: 550 5.