By Roman Loyola
One of the major changes in macOS Sierra isn’t an obvious one, and you may not encounter it until you try to install an app that you didn’t buy from the App Store.
In the Sierra Public Beta, Apple has changed the settings for running downloaded apps. If you really need to run that app and can’t figure out how, it can be frustrating. The settings are found in the General tab of the Security & Privacy system preference.
Note: This article was written using the Sierra Public Beta. It will be updated for each OS update, as well as for the final release in the fall.
Read more here:: How to run apps that are not from the App Store in macOS Sierra