March 21, 2013, 5:06 PM — Here's how you can disable the annoying warning that appears when you go to change a file extension in OS X on your Mac.
1. Open a terminal window.
2. Type in the following command then hit Enter.
defaults write com.apple.finder FXEnableExtensionChangeWarning -bool false
For more, see the original article at the link below.

How to Remove Annoying “Pop Up” Warnings & More in Lion | Amsys



















