Go to the Start Menu in the bottom-left corner of Windows:
When you click to open the Start Menu, type the word "default" and it will start searching:
Select "Default apps" at the top of the search results:
If you scroll to the bottom of the Default Apps settings, you will see the option to "Set defaults by app":
Near the top you will see "Adobe Acrobat Reader DC" and when you click it you will be able to select "Manage":
Click the app next to "PDF":
In the menu that appears, select "Adobe Acrobat Reader DC":
If your previous default was Microsoft Edge it will ask to confirm that you want to change the app and you can click "Switch Anyway":
