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My emails are being rejected - I'm getting messages with the error code 550. What should I do?

There are several possible reasons for this.

Your email is being identified as spam.

If you're getting the message: 550 Message rejected due to sender IP reputation ([86.xx.xx.xx]) this might be because your email is being rejected as spam by the BT network.

This might be happening because:

  • you have a virus on your computer or email server. Try these links to help you identify and clear any problems:




  • your emails are bigger than our maximum size limits
  • you're sending emails to people who haven't opted to receive them

If you're using your own email server, make sure it is not set to Open relay.

There’s a problem with your SMTP authentication.

If you're getting an error message saying Recipient not authorised, you may need to change the SMTP server for the mail account you're sending from.

To do this in Internet Explorer, select: Tools>Accounts>Account name>Properties Servers.

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