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:

1. Launch System Preferences from the Apple menu
2. Choose “Security & Privacy” and then click the “General” tab, followed by clicking the lock icon in the corner to unlock the settings
3. 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

* Newer versions of macOS can allow apps from anywhere with these instructions if the option is not immediately available

This is the same in all versions of Mac OS X with Gatekeeper support, including MacOS Mojave, MacOS High Sierra, macOS Sierra, El Capitan, OS X Yosemite 10.10.x, OS X Mavericks, 10.9.x, and Mountain Lion 10.8.x, where the feature was first introduced.