i downloaded this app to change my background when i login and i tried to open it and it says "your securityprefrences allow insallation of only apps from the mac app store and identified developers" how do i change that
Open System Preferences (under the Apple logo in the Menu Bar). Choose "Security & Privacy". On the "General" tab, check "Allow apps downloaded from --- anywhere".
Please understand the risks involved - I suggest changing this setting back once you got the app you want.
See the heading "How to open an app from a unidentified developer" on this support page. The instructions apply to installer packages and other installable items as well as applications.
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