554 invalid ip for sending mail of domain

A common issue!

The error "554 invalid IP for sending mail of domain" typically occurs when a mail server (MTA) is trying to send an email on behalf of a domain, but the IP address used to send the email is not authorized to send mail for that domain.

Here are some possible causes and solutions:

  1. SPF (Sender Policy Framework) configuration: Check if your domain has a valid SPF record set up. SPF helps prevent spam by specifying which IP addresses are authorized to send emails on behalf of your domain. You can check your SPF record using online tools like SPF Record Checker or DNS Checker.
  2. DKIM (DomainKeys Identified Mail) configuration: Verify that your domain has a valid DKIM record set up. DKIM helps authenticate the sender of an email by adding a digital signature to the message. You can check your DKIM record using online tools like DKIM Record Checker or DNS Checker.
  3. Reverse DNS (rDNS) configuration: Ensure that your IP address has a valid reverse DNS (rDNS) record set up. rDNS helps map an IP address to a domain name. You can check your rDNS record using online tools like Reverse DNS Checker or DNS Checker.
  4. Mail server configuration: Check your mail server's configuration to ensure that it is properly configured to send emails on behalf of your domain. Verify that your mail server is using the correct domain name and IP address.
  5. Blacklisting: Check if your IP address is listed on any blacklists, such as Spamhaus or SORBS. If your IP address is listed, you'll need to contact your ISP or hosting provider to resolve the issue.
  6. Domain authentication: Verify that your domain is properly authenticated with your mail server. This may involve setting up domain keys, TXT records, or other authentication mechanisms.
  7. Mail server software: Check if your mail server software is up-to-date and configured correctly. Outdated or misconfigured software can cause issues with email delivery.

To troubleshoot the issue, you can try the following:

  1. Check your mail server's logs to see if there are any error messages related to the invalid IP address.
  2. Use online tools like Mail-Test or Email-Tester to test your email delivery and identify any issues.
  3. Contact your ISP or hosting provider for assistance with configuring your mail server or resolving any blacklisting issues.
  4. Consult with a network administrator or email expert to help you troubleshoot the issue.

Remember to always follow best practices for email delivery and authentication to ensure that your emails are delivered successfully and not flagged as spam.