mail-tester.com

Need Help Improving My Email Deliverability Score (Mail-tester Issues with Authentication & HTML Body) Hey everyone, I'm trying to improve the deliverability of my emails, and I’ve run into some problems using [mail-tester.com](https://mail-tester.com) and another SMTP test site. I'm currently scoring **8.1/10**, but I'm losing points due to the following issues: * ❌ **Mail Authentication Report:** \-3 points * ❌ **HTML Body Report:** \-2.60 points What’s working fine: ✅ SPF, DKIM, and blacklist checks ✅ No spammy content or short URLs ✅ Message size is 10KB with 39% text ✅ No images, no unsub link (not a newsletter) What I need help with: 1. How do I fix the **Mail Authentication** error? (Is it a DMARC, SPF, or DKIM misconfiguration?) 2. How can I improve the **HTML Body** score to avoid spam filters? If this isn’t the right community for these kinds of questions, please let me know where I should post instead — whether it's a subreddit like r/emailmarketing, r/sysadmin, or somewhere else. Thanks so much in advance for any help!

Email Server Security Tests [*Cross-posted*](https://www.reddit.com/r/selfhosted/comments/1fcau7q/email_server_security_tests/) I host my own email server with security top of mind. So I spend a considerable amount of time hardening it. Here are some publicly available security tests for email servers that I found helpful in validating my security configuration. I hope these are helpful for you too. * [https://mecsa.jrc.ec.europa.eu](https://mecsa.jrc.ec.europa.eu) (Great for testing StartTLS, X509, SPF, DKIM, DMARC, DANE, DNSSEC, MTA-STS) * [https://www.hardenize.com](https://www.hardenize.com) (Great for testing rDNS, PTR, cipher suites) * [https://internet.nl](https://internet.nl) (Great for testing IPv6 and DNSSEC) * [https://checkcybersecurity.service.ncsc.gov.uk/email-security-check/form](https://checkcybersecurity.service.ncsc.gov.uk/email-security-check/form) (Great for testing DKIM, rDNS, PTR) * [https://www.checktls.com/TestReceiver?ASSURETLS](https://www.checktls.com/TestReceiver?ASSURETLS) (Great for testing mandatory TLS enforcement) * [https://www.mail-tester.com](https://www.mail-tester.com) (Great for testing HELO, rDNS) * [https://dane.sys4.de](https://dane.sys4.de) (Great for testing DANE)