due.de

Email infrastructure report · Last checked 28 Jul 2026, 16:03 UTC

Summary

due.de uses Self-hosted / Custom for email and has DMARC configured. It is not catch-all.

Mail provider

ProviderSelf-hosted / Custom self-hosted

Primary MXsmtpin.rzone.de

MX records

Priority	Hostname	IPs
5	smtpin.rzone.de	81.169.145.97, 2a01:238:20a:202:50f0::1097

Authentication

SPF✗ Missing

DKIM? Not detected via common selectors

DMARC✓ Present p=reject

Raw DMARC record

v=DMARC1;p=reject;

Email behavior

Catch-all✗ No

Disposable✗ No

Free provider✗ No

STARTTLS✓ Supported

SMTP response81ms

SMTP banner220 smtpin.rzone.de ESMTP RZmta 55.5.6 ready (mi83)

What this means

This domain is missing SPF, DKIM, which weakens its protection against email spoofing. Adding these records would improve deliverability and reduce the risk of impersonation.

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