How to associate a file with a program in Windows
How does Windows know what program to use to open your file? Microsoft Windows associates programs with the file extensions. For example, Windows Photo Viewer is the default program to open .jpg and other photo extensions. However, what happens when you install a photo program, like Picasa, and all of a sudden your photos are opening in Picasa Photo Viewer? Just as programs can change the file associations so can you! Just follow these simple steps below.
1. Right-click on the file you want to change the file association with and click Properties.
2. In the file Properties click the Change button next to the "Opens with" option. After clicking Change, you'll be given a list of programs to open the file, select the program you want to use and then click Ok or Apply.
Note: If the program you choose is not compatible with the file type repeat steps one and two and choose a different program.
1. Right-click on the file you want to change the file association with and scroll to Open with. After the menu opens, Click Choose default program…, you’ll be given a list of programs to open the file.
2. Select the program you want to use then check Always use the selected program to open this kind of file.
3. Click OK