⚠️ A New Type of Phishing Attack Is on the Rise
We want to alert our clients and the broader community to a rising cybersecurity threat: Microsoft 365 calendar-based phishing scams. These attacks are becoming more sophisticated and harder to spot, targeting users directly through their Outlook or Microsoft 365 calendar. If your business uses Microsoft 365, this is something you need to be aware of—and protected against.
🚨 How the Scam Works
In these scams, cybercriminals send malicious calendar invitations that may look like they’re coming from Microsoft or a trusted vendor. These fake events claim things like:
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You have an outstanding balance on your Microsoft 365 account
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Your M365 services will be suspended or canceled
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Your licenses are up for renewal or verification
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You must take immediate action to avoid service interruption
The invitation typically includes a link to what appears to be a legitimate Microsoft sign-in or billing page—but it’s actually a phishing site designed to steal your login credentials or financial information.
❌ Microsoft Will Not Contact You Directly About Billing
It’s important to understand that Microsoft does not reach out directly to end users or clients via calendar invites, text messages, or phone calls about billing, payment failures, or license renewals. Any legitimate communication about your Microsoft 365 account will come through your managed service provider (MSP)—in this case, Ntegra IT—or through secure and expected Microsoft billing channels, such as the Microsoft 365 Admin Center or official billing notifications sent to account admins.
If you receive a message claiming to be from Microsoft about an urgent billing issue or service cancellation, treat it as highly suspicious—especially if it arrives in the form of a calendar event.
🛡️ How Ntegra IT Helps You Stay Protected
As your trusted IT and cybersecurity partner, we proactively secure your Microsoft 365 environment using a layered defense strategy that includes:
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Blocking external calendar invitations from untrusted sources
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Advanced phishing protection through Defender for Office 365
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Ongoing phishing simulations and user awareness training
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Multi-Factor Authentication (MFA) and Conditional Access policies to prevent unauthorized access
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Real-time threat monitoring and remediation via our managed services stack
If you’re already covered under our NtegraCare Managed Services Agreement, many of these protections are already in place. If not, we encourage you to contact us to learn how we can help protect your team.
✅ What You Can Do Right Now
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Be skeptical of any calendar invite claiming to be from Microsoft or another vendor—especially if it urges urgent action.
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Don’t click links in unexpected invites. When in doubt, open a browser and go directly to the official Microsoft site.
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Report suspicious messages to your IT team or to Ntegra IT if you’re a managed client.
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Train your team regularly on how to recognize scams and phishing attempts.
💬 Need Help?
Ntegra IT specializes in helping businesses secure their Microsoft 365 environment with zero-trust security frameworks, compliance-focused configurations, and responsive, local support. Whether you’re already working with us or exploring new options for protecting your company, we’re here to help.
📞 Contact us today to schedule a risk assessment or to discuss how we can support your cybersecurity goals.
Ntegra IT
Integrating Information Technology with Integrity
