Spam meeting invitations are automatically added to calendar — cannot disable in Outlook for Mac (Legacy)

Hi @Moto Lorne

Thank you for posting your question in the Q&A Forum and sharing the issue you're experiencing with meeting invitations automatically being added to your calendar in Outlook.

I completely understand how frustrating this can be, especially when these unwanted invitations clutter your calendar. Unfortunately, in some versions of Outlook for Mac (Legacy), there isn't a direct option to disable the automatic processing of meeting requests. However, there are a couple of potential solutions you can try: 

Set up a Server-Side Rule 

One possible approach to stop meeting invitations from being automatically added to your calendar is to set up a server-side rule. This can help filter unwanted invitations before they even reach your inbox, preventing them from being added to your calendar automatically. 

Steps to set up the rule: 

• Log in to your account via Outlook on the Web (OWA). 
• Navigate to Settings > Mail > Rules. 
• Click Add a new rule. 

Condition: Select Type, then choose Invitation. 

Action: Select Move to, then choose the Junk Email folder. 

• Save the Rule. 

Switch to the New Outlook for Mac  

If possible, I suggest switching to the newer version of Outlook for Mac, as it offers more control over meeting invitations. The latest version includes more features for controlling how meeting requests are handled. 

To switch to New Outlook for Mac: 

• Open your current Outlook for Mac (Legacy). 
• Look for the "New Outlook" toggle switch, typically located in the top-right corner of the application. 
• Enable New Outlook, which will give you access to a modern interface and additional features for better calendar management. 

If your organization uses Exchange Online, your IT department may be able to configure PowerShell commands on the server side to prevent automatic processing of meeting requests. This could offer a more customized solution to your issue. 

We understand that features like these are important to your productivity, and we value your feedback. If the current options don’t fully meet your needs, we encourage you to submit feedback about the missing feature. Your input helps improve the application for all users. 

You can share your feedback directly with the Outlook product team via Help > Feedback in Outlook or through the Microsoft 365 Feedback Portal. 

I truly hope one of these solutions will help you resolve the issue. If you continue to experience difficulties or have any further questions, please don’t hesitate to reach out. I’m here to assist you.

Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread. 

@Moto Lorne

Is your problem similar to what is reported in this thread for Classic Outlook for Windows?

This issue has been reported to Microsoft and they are investigating. https://learn.microsoft.com/en-us/answers/questions/5597205/prevent-pfishing-calendar-items To submit and in-app incident report from New or Classic Outlook see the comment in that thread from: Hal Hostetler MVP-Outlook MVP Volunteer Moderator Nov 8, 2025, 12:17 PM

SPAM Calendar Events - Update 2025-12-05 - Still an ongoing issue. No update from Microsoft on a general solution.

If your organization has a Microsoft Defender for Office 365 subscription, there are steps your IT Admin can take to mitigate the impact:

https://techcommunity.microsoft.com/blog/microsoftdefenderforoffice365blog/strengthening-calendar-security-through-enhanced-remediation/4456876

If you are in an IT Managed environment, there are Mail Flow Rules that your IT Admin can implement that will block all external Calendar invites (and allow for specific exceptions):

https://learn.microsoft.com/en-us/answers/questions/5558001/how-to-prevent-calendar-invites-from-external-sour