SMTP 554 error

Yahoo Mail 554 delivery error: dd not a valid recipient. What is the Yahoo Mail SMTP 554 error and how do I fix it? How does the 554 error look? {Remote Host error: 554 delivery error: dd This user doesn’t have Yahoo.com Account} {Yahoo 554 delivery error: dd requested mail action aborted} {Message not delivered SMTP Error 554} {554 rejected due to spam URL in content} These error wordings show that the receiver account does not exist, or that the email was rejected, and that the mail delivery has failed. Why am I getting the Yahoo 554 delivery error message? This error usually happens when you send an email to the wrong email address. For a SMTP 554 error, spamming can also be the reason for this problem. Check that your server's IP has not been blacklisted. Request that your IP is whitelisted by the receiving server. If your email contains a spam link, broken images or broken content or any illegal content then you can also receive this error. A receiving server can also reject an email because of something in the From or To headers that it does not like, that identifies your machine as a spam relay. An wrong time setting in the system can also sometimes create this Yahoo error code 554. How to Fix the Yahoo Error Code 554. Check the receiver email address again before you send an email. You may have left out the "@" or a Full Stop sign. Most Yahoo mail accounts end in "@yahoo.com", but older accounts could have a country specific extension, such as "@yahoo.co.uk", @yahoo.es or "@yahoo.fr". Check that you include the correct domain extension, (the ".co.uk" or ".es" part) when you give out your own email address, or when you send an email to a Yahoo Mail/Ymail account. If an email is sent to the wrong domain extension, then it won't be delivered. Confirm from the email recipient that their account still exists. It could be dormant, and therefore eventually removed. Check that your email content does not involve HTML forms or Java Scripts. Check the Yahoo Policy to see if there is content in your mail that is not allowed to send. Try to send the email from another email provide, like Gmail or Outlook, to test and confirm the existence of the receiver mailbox. Most Yahoo Mail 554 errors is simply a result of mistyping of the receiving email address, or because the receiving email address no longer exists. -SMTP Error 554-