Verify MX records are correct and mail can be received

Correct MX record configuration addresses the fundamental technical mechanism that actually enables your domain to receive email at all — this DNS record tells other mail servers which specific server should receive email addressed to your domain, and any misconfiguration here can cause legitimate incoming mail to fail delivery entirely, often without any obvious warning to either sender or recipient.

The genuine verification this check requires goes beyond confirming an MX record simply exists — actually testing that mail sent to your domain genuinely arrives and is retrievable confirms the full, functional mail delivery chain works correctly, since a technically present but misconfigured record can create the appearance of proper setup while actual mail delivery silently fails.

This represents foundational infrastructure that the more advanced email authentication protections discussed elsewhere in this security work — SPF, DKIM, DMARC — all depend on functioning correctly as their prerequisite, since these protections govern how mail gets authenticated and handled, but none of them matter if the fundamental mail-receiving infrastructure itself isn't correctly configured.

Priority values within your MX configuration, where multiple mail servers are listed, deserve genuine attention for organizations with backup or redundant mail infrastructure — correct priority ordering ensures mail attempts delivery to your intended primary server first, falling back to backup servers only when genuinely necessary, rather than an incorrect configuration that could route mail unpredictably or fail to properly utilize backup infrastructure when needed.