How do you fix this error message 550 5.1 1 User unknown?

Solution 1: Confirm the recipient’s email address It sounds too simple, but the wrong email address is the most common issue that causes 5.1. x errors. Check for correct spelling and send the message again if you find an error in the email address. To resend the message in Outlook, see Resend an email message.

How to fix error 550 email?

How do I fix a 550 error?

  1. Check for email address typos.
  2. Check whether the email IP is blacklisted.
  3. Try sending the email after some time.
  4. Try changing your outgoing mail port.
  5. Check whether IP filtering is enabled.
  6. Enable SMTP authentication.
  7. Troubleshoot the SSL method.
  8. Contact your ISP.

What is smtp 550 5. 1 1?

550 5.1. 1 means that the recipient email server believes that the email address does not exist at the destination domain, and therefore has no way to deliver it. Unless you simply made a typo in the email address, this is not something that you can fix, and must be addressed at the other end.

What does 550 5. 1 0 address rejected mean?

The destination email server that generated the 5.1. 0 error won’t accept messages from you (the sender) or messages for the recipient. This can happen if messages from you (your email address, your Exchange Online organization, or even all of Exchange Online) are being blocked by the recipient.

What can be the reason if you receive a user unknown reply to an email you sent?

It is an error code that usually stands for some issue with the recipient server. The most frequent error message is “ User unknown ”. In most cases, this is because the recipient address does not exist.

What does a 550 email error mean?

550 Blocked error or 550 Requested action not taken: mailbox unavailable is an SMTP (Simple Mail Transfer Protocol) error code. Put simply, this message means that the email you sent was blocked by the recipient’s email hosting server, and returned to you.

What is server error 550 in Outlook?

A “550 Authentication is required for relay” error indicates that your email server requires SMTP authentication in order to send outgoing mail, but the email client used to send email has not been authenticated with your username and password.

How do you fix 550 high risk of spam?

Common Solutions To This Error

  1. Limit The Number of Emails Sent Per Hour/Per Day.
  2. Ensure The Contents Of Your Email Don’t Read As Spam.
  3. Verify That Your DNS Security Settings Are Properly Setup.

What is a 550 error in Outlook email?

What does 550 too many invalid recipients mean?

This article provides you with information on email sending error 550 “Too many invalid recipients”. If you are receiving this error it indicates that the email account has been blocked because the account has been sending emails to a large number of invalid addresses.