What Is Causing This Error?
The ‘error 454-5.5.1’ issue often occurs on sites sending emails through an SMTP server. It indicates that the STARTTLS command, which is used to establish a connection between the SMTP server and the email client runs multiple times.
The most common causes of the error include misconfiguration of the email client and server misinterpretation.
In some cases, this error could originate from the recipient’s email client. This can occur if the email client is configured to issue the STARTTLS command multiple times or at the wrong interval. When this happens, you’ll likely encounter the error 454-5.5.1 issue.
Resolving the Error – Solution
To fix this error, first make sure your SMTP server is properly configured. Using the wrong TLS/SSL settings could force the recipient’s email client to repeat the STARTTLS command.
Also, review and ensure the username and password you configured on your SMTP server are correct.
If the error occurs due to misconfiguration of the recipient’s email client, we recommend contacting them to update the TLS settings on their server.
That’s it! Now you know how to fix the ‘Error 454-5.5.1: STARTTLS may not be repeated’ issue.
If you’d like to learn how to troubleshoot other common errors, check out the following tutorials: