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News and updates about the platform

Aug 31, 20265 minDisclaimer

Exclaimer Signature Manager Exchange Edition: support has ended, what remains

Exclaimer's locally installed signature product is discontinued and support ended on 30 September 2024. What that means in operations and which routes remain for companies running their own Exchange and a local Active Directory.

Aug 6, 20266 minE-Mail-Zustellbarkeit / Troubleshooting

Error 550 5.7.515 in Outlook: Why Microsoft Rejects Your Mail and How to Fix It

The bounce 550 5.7.515 means Outlook.com rejected your message because the sending domain lacks valid SPF, DKIM and DMARC authentication. This guide explains what the code means, why Microsoft…

Aug 4, 20267 minE-Mail-Authentifizierung / Compliance

DMARC in 2025/2026: What Google, Yahoo, Microsoft and the BSI Now Require From Your Domain

DMARC is no longer optional. This guide bundles the bulk sender requirements from Google, Yahoo and Microsoft with the BSI recommendation for TR-03182 and p=reject. You learn the timeline, how SPF,…