Kill the duplicates in your Mac's "Open With" menu.
- Make sure your computer has a current Time Machine backup. Using Terminal can be dangerous if you mistype something.
- Launch Terminal from your Applications/Utilities folder.
- Copy and paste this command into Terminal and press return:
System/Library/Frameworks/CoreServices.framework/Frameworks/LaunchServices.framework/Support/lsregister -kill -r -domain local -domain system -domain user
- Reboot or force-quit Finder.
