Email not arriving or landing in spam: SPF, DKIM, DMARC and deliverability

I find out why your company's email lands in spam or bounces, set up SPF, DKIM and DMARC, check the domain's reputation and blocklists, and keep watching so it does not happen again.

Typical causes

No DKIM, or SPF with errors and over the lookup limit.
DMARC missing or set without reports, and the domain is being spoofed.
The website, CRM or accounting system sends mail on behalf of the domain but is not included in SPF and DKIM.
The domain or the hosting provider's IP is on blocklists.
Bulk mailings from a regular mailbox.
Old DNS records left by a previous provider.

What I do

Audit DNS and every sending source: Microsoft 365, Google, website, CRM, scanners and printers.
SPF, DKIM, DMARC with reports, gradually up to a strict policy.
Blocklist checks and delisting requests.
Message trace in Exchange Online: where the message got stuck and why.
Anti-spam and anti-phishing protection, quarantine, user reports.
Migration to Microsoft 365 if the hosting itself is the problem.

The result

Mail from your domain is signed and passes the checks at Gmail, Microsoft and corporate filters. Spoofed mail in your domain's name is rejected. You see reports on who sends mail on your behalf.

Questions and answers

Why does mail land in spam when it used to arrive?

Gmail and Microsoft have tightened sender requirements: without DKIM and DMARC mail goes to spam more and more often. The hosting provider's IP may also have changed, or a new sending service appeared.

What is DMARC and why do I need it?

A rule for what to do with a message that fails SPF and DKIM, plus reports. Without it your domain can be spoofed and you will never know.

Can this be done without migrating the mail?

Yes. DNS records and sending sources can be set up with any hosting. I suggest a migration when the hosting itself is the problem.

Tell me which mail is not arriving and where, and send a bounce message if you have one. I'll take a look and tell you what is wrong.

hello@miraops.io