// 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
5 guides · tag MX
| Problem | In short | Tags | |
|---|---|---|---|
| No MX record on your domain | MX records tell the world where to deliver email for your domain. Without them, you cannot receive replies, and some receivers distrust your emails. | Fix it | |
| 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 | |
| Email records lost after moving your domain or DNS host | You moved your domain, website or DNS to a new company and email stopped working. Often the email records were simply not copied. Here is how to restore them. | Fix it | |
| Protect domains that never send email | Spare domains, old brand names and parked domains can be used by scammers to send fake emails. Three small DNS records tell the world they never send email. | Fix it | |
| "450 4.1.8 Sender address rejected: Domain not found" / "553 5.1.8 Domain of sender address does not exist": fix | The receiver could not find your sender domain in DNS. Usually a typo, a local domain like .local, or a domain with no A or MX record. | Fix it |
Not sure what is wrong?
Send a test email or scan your domain: the report tells you which problem you have.