Gatekeeper is new security feature starting in Mac OS 10.8. See https://support.apple.com/en-us/HT202491 for more information about Gatekeeper features and benefits.

If you are unsure what version of the Mac OS you are running, see http://its.uiowa.edu/support/article/101460

You can find Gatekeeper settings in System Preferences > Security & Privacy > General.

By default Gatekeeper will only open apps purchased and downloaded from the Mac App Store or from a list of “identified developers” that have been given the ok from Apple by obtaining an unique Developer ID.  To install other apps, select the option to install from Anywhere.

Highlighted - Anywhere option.

Note: In most cases, Gatekeeper may only need to be disabled temporarily in order to install and initially launch an application.  After that, Gatekeeper can be re-enabled to only allow applications from the Mac App Store and identified developers.

Article number: 
4038
Last updated: 
July 19, 2016
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