How to change your default PDF viewer on your computer:
- Click on the Start menu and start typing Default apps.
- Click on that option when it appears in the list.
- On the right side of the window, scroll until you can see & click on the text link for Choose default apps by file type.
- On the right, locate the hidden scroll bar and scroll down until you see .pdf in the very left column.
- To the right of .pdf, click on the shown option (probably Edge).
- From the drop-down list select either Adobe Acrobat Reader DC or Acrobat DC.
- You can now close the Settings window.
Your PDF files will now open in the app of your choice.