Hi Takahe! This is Benpella . I'm a fellow Outlook.com user and I'm sorry to hear about the issue. If you're using Outlook on Windows 11 and the option to send email reminders for calendar events is missing, you can try the following steps:
Verify your Outlook version: Ensure that you are using the latest version of Outlook on your Windows 11 computer. Updating to the latest version may introduce new features or resolve any known issues.
Check your calendar reminder settings: Open Outlook and go to the calendar view. Select a calendar event, right-click on it, and choose "Open" or "Edit." In the event details window, look for the "Reminder" section. Make sure that the "Reminder" checkbox is checked, and check the available options to see if email reminders are listed.
Customize reminder options: If the email reminder option is not available in the event details window, you can try customizing your reminder options. Go to the "File" menu in Outlook, select "Options," and then choose "Calendar" or "Advanced Calendar Options." Look for the reminder settings and see if there are options to enable email reminders. Ensure that the "Default reminder" option is selected and set to a suitable time period.
Create a new calendar item: If the above steps don't work, you can try creating a new calendar item and check if the email reminder option is available. Click on "New" or "+" to create a new event in your calendar and check if the email reminder option is present in the event details window.
Repair or reinstall Outlook: If none of the above steps resolve the issue, you may consider repairing or reinstalling Outlook. Go to the "Apps & features" section in Windows Settings, find Microsoft Outlook, and choose the option to repair or uninstall and reinstall the application.
Here is a step by step product on how to go about it
https://learn.microsoft.com/en-us/outlook/troub...
My warm regards
Benpella