Email

This section covers business email from the administrator’s side: why a message lands in spam, how to read its headers, how to set up SPF, DKIM and DMARC, and how to let scanners or applications send mail. The articles link to the site’s tools to check a domain or analyze a message.

30 articles by topic

October 2026

4 articles

Email28 October 2026 · 5 min read
Exchange Online: The End of Password-Based SMTP AUTH, and Your Scanners, Printers and Apps
Exchange Online turns off password-based SMTP AUTH by default at the end of December 2026: find the scanners, printers and apps that depend on it, then migrate.
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Email28 October 2026 · 5 min read
Reading Email Headers: Received, SPF, DKIM, DMARC
Where to find headers in Outlook, Gmail and Thunderbird, how to read Received, Authentication-Results and DKIM-Signature, and spot spam or spoofing.
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Email3 October 2026 · 4 min read
Emails Going to Spam or Bounced: A Troubleshooting Method
Read a bounce message, analyze headers, check SPF/DKIM/DMARC, reputation and reverse DNS: a step-by-step approach to find the cause.
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Email3 October 2026 · 6 min read
SPF, DKIM and DMARC: a Configuration Guide
What each DNS record does, ready-to-adapt examples, common pitfalls and a step-by-step rollout plan up to a DMARC reject policy.
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