Dolphin Default program

[Aleron Ives]

Windows probably isn't aware of it, because Dolphin doesn't create registry entries on its own. You'd need to use the "Browse" function to select a program manually by going to the folder where you extracted Dolphin and selecting Dolphin.exe as the program you want to use to open ISO files. After that, Dolphin will always appear in the list of programs when you try to associate a specific extension with a specific program.