How to troubleshoot when an extracted app file can’t be opened
Mac Apps which are distributed through websites other than the Mac App Store are usually distributed in DMG or PKG format. But some of them are compressed in ZIP format. In the cases, you can’t launch the app which is extracted using Bandizip with a message “The app can’t be opened because it is from an unidentified developer.” as below.
This is caused by the App Sandbox in macOS. To solve the problem, right-click the app icon and select “Open” as below.
If you still can’t solve the problem, you may unzip the app file with Mac Finder instead.