I will provide instructions on that right away, I just need to know one thing! Which operating system are you using? Windows 7, 8, 10? Mac?
Open the folder containing the file you want to change,
Right-click the file, and scroll over or click "open with" depending on if there is a menu there or not...and click "choose default program"
Find the program in the list you want to open the file with, or if it is not on the list, click "other programs" and find the program.
Right click the file you want to open(or control+click if you have a single button mouse), and click "get info"
In the middle of the window, "open with" dropdown menu, choose a program to open with! It is that easy. :)
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