MX points to an IP address
Check id: mx.points_to_ip · fix effort: low
What it means
Your mail server entry uses a bare IP address, which breaks the standard. Some senders will refuse to deliver.
The technical detail
RFC 5321 5.1 requires MX targets to be hostnames. IP literals are undefined behavior.
How to fix it
- Create a hostname (e.g.
mail.yourdomain.com) pointing at the IP, and use that in the MX record.
Does your domain have this problem?
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