> For the complete documentation index, see [llms.txt](https://docs.stoik.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.stoik.io/cyber-best-practices/de/harten-sie-ihre-umgebung-ab/email-authentication.md).

# E-Mail-Authentifizierung

Die E-Mail-Authentifizierung schützt Ihre Domain vor Spoofing und Phishing, indem sie empfangende Mailserver verifizieren lässt, dass eine Nachricht tatsächlich von Ihnen stammt. Stoïks External Scan markiert Domains, denen diese Einträge fehlen oder die sie falsch konfigurieren.

Beides konfigurieren:

* [Was ist SPF und wie konfiguriere ich es?](/cyber-best-practices/de/harten-sie-ihre-umgebung-ab/email-authentication/what-is-spf-and-how-do-i-configure-it.md): legt fest, welche Server berechtigt sind, E-Mails im Namen Ihrer Domain zu senden.
* [Was ist DMARC und wie konfiguriere ich es?](/cyber-best-practices/de/harten-sie-ihre-umgebung-ab/email-authentication/what-is-dmarc-and-how-do-i-configure-it.md): teilt den empfangenden Servern mit, was mit Nachrichten zu tun ist, die die Authentifizierung nicht bestehen, und liefert Ihnen Berichte.


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