Why can't my Mac application be opened?

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If you are seeing the message, “The application [Application Name] can’t be opened," Gatekeeper has most likely flagged the program as not coming directly from the App Store or being from a list of Identified Developers.

You can approve these apps on a one-by-one base by:

  1. Control-clicking, or right-clicking, the application
  2. Selecting Open
  3. Choosing Open on the following dialog

You can also turn off app verification if you have administrator rights, but be aware this is the less secure option, and is not recommended. This can be accomplished by doing the following:

  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.”
  4. Accept the security warning and Allow.

You can now launch any app from any location or developer without a prompt.