Spam calendar events appearing

Marcelo -

Your solution does not work and is not accurate. Please check your solutions prior to posting. It only causes confusion.

Hi Claire,

Thank you for reaching out and sharing your concern about spam calendar events appearing in your iCal that seem to be synced from your Outlook calendar. I understand how confusing and frustrating it can be to see unwanted events show up without any trace in your actual Outlook account or inbox.

This issue typically arises when spam calendar invitations bypass traditional email filters and get injected directly into your calendar through third-party subscriptions or event summaries from email. Even if you don’t see them in your Outlook inbox they may still appear due to calendar sync settings or shared calendar links.

To resolve this you can take the following steps:

First open your Outlook settings and disable the feature that automatically adds events from email. You can do this by going to Settings select View all Outlook settings select Calendar click Events from email and selecting “Don’t show event summaries in email or on my calendar” for each category. This helps prevent future spam events from appearing.

Next check your iPhone or iPad settings for any Subscribed Calendars under Settings select Calendar select Accounts. If you find unfamiliar subscriptions delete them. These are often the source of spam events that bypass Outlook entirely and show up only on your Apple calendar.

Also avoid interacting with these spam events don’t accept, decline or click any links. Instead delete them directly and report them as junk or phishing if possible. In Outlook Web or Desktop you can right-click the event and choose Report as Junk or Report as Phishing.

Have you noticed if these events are recurring from a specific sender or domain? That could help in setting up a rule to block them more effectively.

I hope this answer is helpful if you have further questions feel free to reply back

Regards,

Marcelo

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