MailFixIt

Mailgun email configuration guide

Mailgun: inbound routes not receiving mail

Mailgun MX records are for inbound receiving and Routes; an outbound-only Mailgun sending domain does not need them.

Problem description

A provider setup symptom may look like:

Mail reaches the Mailgun receiving domain, but no inbound Route action runs.

Check the sending domain

What this usually means

Mailgun receives mail only for a domain or subdomain configured for inbound Routes. Publishing Mailgun MX records is not required merely to send outbound mail.

Fix it

  1. Confirm that you intend to receive mail with Mailgun Routes and identify the exact receiving domain or subdomain.
  2. In the matching Mailgun domain and region, copy the inbound MX records and publish them at that exact DNS name.
  3. Remove competing MX records only from this dedicated receiving name. Do not replace your business mailbox MX records unless Mailgun should receive all company mail.
  4. Create or enable a Route whose expression matches the recipient and whose action forwards, stores, or posts the message to the intended destination.
  5. Check the public MX answer, send a new test, then inspect Mailgun logs and the Route destination.

Common mistake

Pointing a subdomain such as mg.example.com to Mailgun does not route mail addressed to [email protected]. Conversely, replacing the apex MX can divert ordinary employee mail away from its mailbox provider.

What MailFixIt can check

MailFixIt can expose the public MX route and conflicts. It cannot run or inspect a private Mailgun Route or webhook.

Use the related MX guides if DNS still points to an old provider or the receiving hostname is wrong.

Frequently asked questions

What does MailFixIt check for Mailgun?

It can show whether the receiving hostname publicly routes to Mailgun and whether other MX records conflict. It cannot inspect Route expressions or webhook delivery.

Should I replace every existing DNS record with the provider values?

No. Confirm the exact record type and owner, preserve unrelated legitimate services, and change only the provider-controlled record required for the intended mail route.

Related email diagnostics

Email delivery delayed or rejected after a DNS migrationDiagnose email that stopped arriving after a DNS change. Compare public MX records with the intended provider and avoid false alarms for mail gateways. SPF is not configured for the envelope sender domainDiagnose SPF missing on a bounce or MAIL FROM subdomain. Check the exact envelope domain, add only authorized senders, and verify safely. DKIM public key record is invalid or revokedDiagnose an invalid or revoked DKIM public key record. Check the exact DKIM selector in public DNS before replacing a sender-provided key.

Primary sources: Mailgun official setup guidance.