When you have files that are specific to your application that when click upon the file your application will open, this is where you set up the associations.
Add New Association:
Description: A description of the extensions association
File Extension: The file extension to associate (IE. .txt)
Icon Filename: The location of the icon file to display for this association (IE MyProg.ico)
App Filename: Application used to open the associated file extension (IE MyProg.exe)
Reg Entry: Entry name to place into registry to define association (IE MyProg.Datafile)
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