You can learn a lot about email troubles by looking at the bounceback message you receive.
- User/Domain/Address Does Not Exist
If you receive this error message, your email was sent properly but the destination does not exist as entered. There could be a typo in the destination email address, or there could be a problem at the recipient's end.
Blacklisted, Blocked, or Rejected Messages
It is possible that your address, server, or domain has been blacklisted. Blocking and rejecting are possible, but it is most likely that blacklisting is the culprit. If this continues, submit a ticket for our help in resolving this issue.
- Specific Error: "Sorry, you are sending to/from an address that has been blacklisted."
Please submit a ticket for our help in resolving this issue.
- Specific Error: "SMTP error from remote mail server after MAIL FROM:: host gateway.websitewelcome.com I was unable to send this e-mail because this domain ( gmail.com / etc.) has been black listed due to spam or forgery."
A script is attempting to send from a remote (third party) domain, but it is designed to send from a local server instead. You should try using an email address that is hosted locally rather than one that is hosted remotely. You could also edit the script to use SMTP via the remote server.
- Other Blacklist/Blocked Messages
If you've received an error relating to blacklisting or blocking that has not been covered here, please submit a ticket.
550 errors are related to the relay of the email from one email node to another.
- 550 "Access denied - Invalid HELO name"
This is usually caused by incorrect settings in your mail client.
- 550 "Dictionary Attack"
Your mail client has sent the wrong login password too many times, and the mail server is closing the connection because it identifies this as a security attack. You need to make sure you have the correct password for the email account, entered correctly. You will be locked out of the server for one hour from the time of the 550 error.
- 550 "SMTP Error" or 550 "Sender verify failed"
Your mail server isn't correctly configured to handle your domain's mail. Your MX record or DNS records may have been incorrectly edited, or you might have set up a remote mail server and not edited the server address in your mail client's settings. For further reading, try this article about MX records, or this article about DNS zones in cPanel, or this article about DNS zones in WHM.
- 451 "Error while writing spool file"
This is normally a temporary error which will resolve itself, but it could also be a mistake in your email client's settings. Verify that your SMTP settings are correct.
Other Error Messages
If you receive other error messages, please submit a ticket.