Upgrade for Live Support

All of our paid plans come with access to our highly experienced technical support team.

  • Contact us via Email, Phone, or Ticket
  • Detailed Explanation of Your Lookup Results
  • Guidance to Help Resolve Your Problems
  • RFC Compliance Best Practices
  • Blacklist Delisting Support

Let our experts help you resolve your mta-sts issue!

Get Mta-Sts Support
LLMSTXT
MTA-STS
ROBOTSAI
TLSRPT
BIMI
DMARC
DKIM
DOMAIN
DNS
HTTP
HTTPS
DOMAIN BLACKLIST
TCP
SMTP
BLACKLIST
CNAME
WHOIS
SPF

MTA-STS Syntax Check

What you see when your domain has this problem
MTA-STS Record Syntax Invalid Details area Ignore
Add mta-sts monitor for 195.142.105.19

More Information About Mta-Sts Syntax Check

This error indicates that there is a syntax issue with the MTA-STS DNS record that is published for the domain.

MxToolbox Delivery Center

This is one problem. Inbox providers check every layer.

Gmail, Yahoo! and Outlook check your email at several layers before it reaches the inbox. Delivery Center monitors and manages every one of them, so you find and fix problems before they cost you delivery.

  • DMARC, SPF & DKIM
  • Blacklists
  • Inbox Placement
  • Spam complaints
  • Impersonation protection
  • BIMI
  • Mailflow
  • Email MarketersTest inbox placement and stay inside bulk sender spam-rate limits.
  • DMARC AdoptersSee every sender and know when it's safe to enforce.
  • IT Email AdministratorsCatch DNS, authentication and mailflow changes with alerts.
See Delivery Center

$129/mo · 30-day money-back guarantee · Compare all plans