Microsoft Mandates Strong Email Security Protocols for 500 Million Outlook Users Worldwide
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You Have 16 Days To Comply — New Rules Impact 500 Million Outlook Users
Microsoft has announced a significant change to its email security protocols, which will impact 500 million Outlook users worldwide. As of May 5th, Microsoft will require all bulk senders using the Outlook.com platform to implement strong email sender authentication in order to prevent spoofing, phishing, and spam activity.
In a nutshell, here’s what you need to do:
* Collect DMARC reports
* Configure SPF and DKIM alignment for major senders on your behalf
* Set your DMARC policy to enforcement (either “quarantine” or “reject”)
* Monitor your domains constantly and run regular checks
Failure to comply with these new rules will result in non-compliant emails being rejected. The clock is ticking, as you only have 16 days left to get it done.
Microsoft’s decision comes after Google introduced mandatory strong email sender authentication for Gmail users, which led to an “unprecedented improvement” in the fundamental security of email. In fact, within just 12 months, there was a:
* 65% reduction in unauthenticated messages sent to Gmail users
* 50% increase in bulk senders following secure practices
* 265 billion fewer unauthenticated messages sent
Don’t underestimate the urgency of this situation! Whether you’re running a small business or a large organization, it’s crucial that you prioritize DMARC protection.
So, what can you do? First and foremost, ensure that your domain is set up to receive DMARC reports. This will help you visualize problems and prioritize the results. Second, choose a reliable DMARC provider that gets you quick results but also helps you monitor and address issues in real-time.
Don’t risk being locked out of Outlook by ignoring these new rules!
Source: https://www.forbes.com/sites/daveywinder/2025/04/19/you-have-17-days-to-comply—new-rules-impact-500-million-outlook-users/
