Thank you for reaching out to the Microsoft Q&A forum and sincerely apologize for the inconvenience you're experiencing.
Based on your description, here are recommended solutions you can try after remove or decline event to avoid fake Microsoft event invitations.
Block the Sender
- Locate the original invitation email in your inbox.
- Right-click the email and select Block sender to prevent future messages.
Report the Invitation as Phishing
- Open the email associated with the event.
- Click the More actions menu (three dots) and select Report phishing. Outlook will send information to Microsoft to improve the filters.
Create a Mail Rule to Filter Suspicious Invitations
- In Outlook Desktop App > Tab Home > Create Rule..
- Create a rule to automatically move or delete emails that contain suspicious keywords commonly found in fraudulent meeting invitations you've received.
(You can choose Move to Junk Email folder or Delete Items)
I hope this information will be helpful and provide some support in resolving your concerns. If you need more detailed guidance on any of these steps or have additional information, let me know in the comment section.
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