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Gatekeeper is an application level security feature on the Mac that aims to prevent unauthorized and unidentified apps from being launched in OS X, thereby preventing potential security problems like exploits or trojans from running on a Mac. The feature is most often encountered when an app has been downloaded from the web, and upon attempting to launch the app a warning dialog will prompt the user with a message saying something along the lines of “This app can’t be opened because it is from an unidentified developer“. We’ve covered how you can get bypass that error message on a case-by-case basis by using the right-click “Open” trick, but the latest version of OS X brings another option which may be easier for some users to selectively launch apps and bypass Gatekeeper. This is advantageous because users can continue to retain the strict security preference of leaving Gatekeeper enabled and intact, which is generally recommended.
Bypass Gatekeeper App Launch Warnings from System Preferences
This solution is temporary, providing a per-application launch bypass. It does not disable Gatekeeper in OS X.
Attempt to launch the application in question, encountering the normal “can’t be opened” message, then click “OK”
Launch System Preferences by choosing it from the Apple menu
Select the “Security & Privacy” control panel, and go to the “General” tab
Under the “Allow apps downloaded from:” look for the following message: “appname.app was blocked from opening because it is not from an identified developer.”
If you trust the application and want to launch it bypassing Gatekeeper, click “Open Anwyay”
The full Security preference panel looks like the following, with Open Anyway highlighted within the Gatekeeper section.
If the “Open Anyway” option is not visible then you likely must unlock the security preferences by clicking the little padlock icon in the corner and entering an administrative password.
Choosing “Open Anyway” will launch the application in question directly from Security System Preferences, and you’ll be able to use it as normal. This approach is obviously slightly more time consuming than using the right-click Open trick, but it may be advantageous for certain users in select situations.
Gatekeeper is really aimed at protecting novice and average Mac users, while advanced OS X users who are more comfortable with things may find the warnings to be intrusive or annoying. If you don’t want to receive the warnings at all, you can simply disable Gatekeeper completely through the Security System Preferences by choosing “Anywhere” from the allow apps list.
This feature was first introduced to the Mac with OS X Mountain Lion, but the “Open Anyway” option inside the Security preferences is new with OS X Mavericks.
