Temporarily Get Around “App Can’t Be Opened” Gatekeeper Alert Message
This is probably the best option for most users, since it maintains some security:
- Right-click (or control-click) the application in question and choose “Open”
- Click the “Open” button at the next dialog warning to launch the app anyway
If you get tired of constantly right-clicking apps to open them, return to pre-Mountain Lion levels of app security by turning off Gatekeepers app verification completely.
Disable GateKeeper’s Unidentified App Developer Prevention Completely
This is generally best for advanced users who know what apps to trust and not to trust:
- Launch System Preferences from the Apple menu
- Choose “Security & Privacy” and then click the “General” tab, followed by clicking the lock icon in the corner to unlock the settings
- Look for “Allow applications downloaded from:” and choose “Anywhere”
- Accept the security warning and allow
- You can now launch any app from any location or developer
