MacOS: Disable “{appname} can’t be opened because it is from an unidentified developer”

MacOS Sierra has a feature called “Gatekeeper” that will present a message that says “{appname} can’t be opened because it is from an unidentified developer” if you try to run an application that is outside of the app store or from a developer that is not familiar.

If you know what you’re doing and don’t like to be bothered with this message, you can disable the Gatekeeper feature using these steps.

Option 1 – Permanently Disable Gatekeeper

1. From “Utilities“, open “Terminal“.
2. Type the following, then press “Enter“:
   sudo spctl --master-disable
3. Type your administrator password, then press “Enter“.
4. Select the “Apple” menu, then choose “System Preferences…“.
5. Open “Security & Privacy“.
6. In the “Allow apps downloaded from:” area, select “Anywhere“.

Option 2 – Disable On Specific App

1. Hold the “Control” key and click the app icon.
2. Select “Open“. The warning will still appear, but you will be allowed to proceed with opening the application.

Option 3 – Disable On Specific App From Prefs

1. After attempting to open the file, Select the “Apple” menu, then choose “System Preferences…“.
2. Open “Security & Privacy“.
3. Select the lock at the bottom of the screen to allow editing of settings.
4. Type your admin password if prompted.
5. In the “Allow apps downloaded from:” area, select “Open Anyway“.