I I got this answer from here.
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Choose a file that has the same extension as the other files that you extensively use and right click on it. Example: .mov extension (video)
- Select “Get Info” from the list shown in the pop-up
- Choose Open With and expand the drop down to choose an app
- Select Change All… option under Use this application label box
- Finally a pop-up asking “Are you sure you want to change all similar files to open with the application” comes up, select continue to save the settings
- Now the next time you open a file, it is opened using the default application of your choice
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Simple but it required me multiple searches to find the right answer.
