Email troubleshooting guides
Proton Mail setup guides, organized by problem
Browse Proton Mail MX, SPF, and DKIM setup guides for custom domains.
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Proton Mail: DKIM record not verifyingFix Proton Mail DKIM by publishing all provider-issued CNAME selectors, letting Proton verify them, and checking a newly signed message.
Proton Mail: MX records not receiving mailProton Mail: MX records not receiving mail. Follow the checks that directly address this provider configuration.
Proton Mail: SPF record for provider sendingProton Mail: SPF record for provider sending. Follow the checks that directly address this provider configuration.
Primary sources: Primary technical reference.