What should I do if my emails are bouncing back to the sender?

If you receive a bounce-back message, first check the error details in the returned email. For example, an error such as 550 5.1.1 Recipient address rejected usually means the recipient address is not configured to receive emails or the address is invalid.

If the bounce message is related to emails you did not send, or you cannot find the sent record in webmail, the account may have been used through SMTP from a remote server after a phishing or credential compromise. In this case, reset the affected email password immediately, avoid clicking suspicious links, run a full virus scan on the PC or laptop used to access the email, and monitor the account. If needed, also add or update your SPF and DKIM DNS records and continue monitoring the result.

Updated on: 04/05/2026