// how to fix
Not sure what is wrong?How to fix email problems
Your test or scan found a problem? Find the matching guide below: what it means, why it matters, and how to fix it step by step.
Bounce 40
DNS 36
DMARC 33
Reputation 33
SPF 30
DKIM 27
Gmail 19
Security 19
Blacklist 18
Content 14
Headers 11
Mailing list 11
Spam score 11
Reverse DNS 10
Microsoft 365 8
Outlook 8
Mail server 7
MX 5
Yahoo 4
TLS 3
Apple 2
Google Workspace 2
BIMI 1
E-commerce 1
GMX 1
WordPress 1
Zoho 1
3 guides · tag TLS
| Problem | In short | Tags | |
|---|---|---|---|
| Protect your incoming mail with MTA-STS and TLS-RPT | MTA-STS forces other servers to use encryption when they deliver email to your domain. TLS-RPT sends you reports when that fails. Both are optional but recommended. | Fix it | |
| Emails sent without TLS encryption (STARTTLS) | Your server delivered the email in clear text, without encryption. Gmail flags this with a red padlock and expects bulk senders to use TLS. Turn on STARTTLS. | Fix it | |
| "530 5.7.0 Must issue a STARTTLS command first" (and "451 5.7.3 STARTTLS is required"): how to fix it | The server requires an encrypted connection before it accepts your email. Turn on TLS in your app, printer or server and use the right port. | Fix it |
Not sure what is wrong?
Send a test email or scan your domain: the report tells you which problem you have.