Installing software that is not from the App Store or an identified developer will open a dialog screen asking if it is alright to install from them. One needs to click yes and then go into System Preferences -> Security & Privacy and click an ok there as well.
To make the process easier to automatically give permission to install the software you have downloaded you can open terminal.
In Applications -> Utilities and open Terminal. Add the following code. Then press Enter and add your Mac administrator password, and press Enter again.
sudo spctl --master-disable
Open the System Preferences -> Security & Privacy – General Tab.
Select the Anywhere option. The next time it will be a lot easier installing software in OSX.
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