Mac OS X defaults to preventing applications that didn't come from a verified source or from the Mac App
Store. As Mockplus didn't come from the Mac App Store, the Mockplus demo package cannot be opened on OS
To fix this issue, just follow the below steps:
1). Open the Security & Privacy control panel: Apple menu > System Preferences... > Security &
2). Click the Lock icon saying “click the lock to make changes”.
3). In the section Allow applications downloaded from, select Anywhere > A warning message appears.
Click the button Allow From Anywhere to confirm the new configuration.
4). Click the Lock icon at the bottom left of the window to save the changes.