MailFixIt

Proton Mail email configuration guide

Proton Mail: MX records not receiving mail

Incoming mail is not reaching Proton Mail because the public MX route or destination account is incomplete.

Problem description

A provider setup symptom may look like:

MX records not receiving mail after a provider DNS change.

Check the sending domain

What this usually means

Incoming mail is not reaching Proton Mail because the public MX route or destination account is incomplete.

Fix it

  1. In Proton Mail, verify the custom domain and create every address or user before changing MX. Copy the complete MX set from Settings → Domain names for that domain.
  2. Make sure the custom domain is active and all required recipients exist.
  3. Publish the full MX set for the exact domain in the authoritative DNS zone.
  4. Remove old mailbox-provider MX records only if Proton Mail should receive directly. Preserve an intentional security gateway and fix its next hop instead.
  5. After DNS caches expire, inspect the public MX answer and send a new message to an existing recipient.

Common mistake

Changing MX before creating recipients can lose mail. Mixing MX records from unrelated mailbox providers can make delivery intermittent.

What MailFixIt can check

MailFixIt can expose missing, conflicting, or invalid public MX records. It cannot activate Proton Mail or create recipient accounts.

Use the related guides for the exact DNS or authentication warning, then repeat the same mail-path test.

Frequently asked questions

What does MailFixIt check for Proton Mail?

It checks the public MX record and visible conflicts. The provider console and a new delivery or message header must confirm the complete result.

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: Proton Mail official setup guidance.