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Set up Microsoft Defender for Office 365
In this post I want to give you a summary about what Microsoft Defender for Office 365 is exactly and...
Office 365 Cross-Tenant Mailbox Migration (Corporate Merger Scenario)
Because of a corporate merger from the parent company of a subsidiary, I need to move the user mailboxes from...
Email Authentication by using DMARC, DKIM and SPF
In this post I want to show how you can prevent that your email domain is abused for email spoofing...
Set up DMARC (verification) for Postfix on Ubuntu
Last week I wrote a post about how to set up SPF and DKIM for Postfix on Ubuntu, today I...
Set up DomainKeys Identified Mail (DKIM) for Exchange Online
Either you can set up DKIM by using the Microsoft 365 Defender portal or manually by using PowerShell. First I...
Configure Postfix to block and reject Unsolicited Messages or Spam
Below I want to show how to configure the built-in options for Postfix to prevent unsolicited commercial emails (UCE) or...