How to Change / Set a default program in Windows 10
Instructions for changing the default program associated with a file type.
1) Bring up the Default Programs menu by searching for Default Programs in the Windows search bar.
2) Select Set your default programs.
3) Select the program you wish to set as the default from the list on the left-hand column. For this example, we will set Adobe Acrobat as the default program to open PDF files.
4) After selecting, click Choose defaults for this program from the options at the bottom of the window.
5) A list of file types/extensions the program can be associated with will appear. Find the file type you wish to have associated with your program by default. In our example, we are selecting ".pdf" from the list of extensions. Check the box of the left-hand side of extension name.
6) Click Save in the lower right-hand corner of the screen. The program and file type you selected should now be associated by default.