The Wrong Way to Do This
- Right click on the file
- Select "Open With", and then select "Other...", choose the application
The RightWay to Do This
- Right click on the file, choose "Get Info"
- A left panel will show up. Select "Open with:" and then check the specified application.
- Click on "Change All.."
- Click "Continue", and now you have a MAC OS which always open epub file with Adobe Digital Editions.
Because the way to do this in MAC OS is ridiculously against the common sense.