Outlook on Mac, how to stop signature automatically being added to calendar

Hi Logan Runger, 

Welcome to Microsoft Q&A Forum!

Have a good day and I hope you're doing well!

Thank you for reaching out about the issue you're experiencing with signatures automatically being added to calendar events in Outlook on your Mac. I completely understand how frustrating this can be, especially when it disrupts your workflow and makes managing your calendar less efficient. Rest assured, I'm here to help and appreciate your patience as we troubleshoot this together. 

To better assist you, I've replicated the scenario in a virtual environment using Outlook for Mac. I created a signature following the standard steps: going to Outlook > Preferences > Signatures (you can find detailed guidance here: Change or update an email signature in Outlook for Mac - Microsoft Support. In my tests, everything worked smoothly. When I created a new calendar event, the signature did not appear automatically in the event description or notes. 

That said, I suspect that in some cases, when creating a calendar event on Outlook for Mac, it might open an email-like window, causing Outlook to treat it as an email composition and inadvertently add the signature. To help narrow this down, could you please try using the Outlook web version (at outlook.office.com) to create a signature and then test adding a calendar event? I'd love to know if the signature gets added there as well. It could indicate if the issue is specific to the Mac app. 

Additionally, if you could provide a screenshot of the "Signatures" section in your Outlook on Mac (showing how you've set them up), that would be incredibly helpful. In the meantime, let's try a few more steps: 

1. First, try deleting the signature that's currently being linked to your calendar events, then recreate it from scratch. Remember to fully quit Outlook (not just close the window) and restart it to ensure the changes apply. 

2. If the issue persists, go back to the Signatures preferences and set both "New messages" and "Replies/forwards" to "None" before creating a new event. Then, test to see if the signature still appears. 

Please share any additional details you can, such as your Outlook version number, the type of account you're using (e.g., Microsoft 365, Exchange, or Outlook.com), or any other observations about when this happens. This will help us pinpoint the reason more effectively. 

Please be assured that even if our initial suggestions don't resolve the issue right away, your feedback is incredibly valuable to us. With a bit more detail, we'll collaborate to find the best solution tailored to your needs. 

Thank you once again for your time and input. I'm looking forward to your response and am committed to getting this sorted out for you. 

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I am experiencing the same problem. Outlook for Mac Version 16.100 (25081015).

Following some of your steps, it does not reproduce in Outlook web version. Even without creating a new signature.

I was able to get it to stop showing up in events by unselecting the signature under Replies/forwards. But then that also affects email replies/forwards which I want to keep the signature on.