Open the Start Menu
Click on the Start button located at the bottom left corner of the screen.
Search for “Default Apps”
Type “Default app settings” into the search bar. As you start typing, you should see the search results appear automatically.
Select “Default Apps” from the search results. It should be listed under “Best match.”
Change the Default Mail Application in “Default Apps”
In the Default Apps settings window that opens, scroll down until you find the “Email” section.
Click on the current default email application (usually set to “Mail”). A list of available options will appear.
Choose “Outlook” from the list of available email applications. If Outlook is not listed, make sure it is installed on your computer.
Close the settings window. Outlook will now be the default app for email. From this same settings page you can also choose other default apps for your browsers and other media.
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