Mac OS security restricts applications from accessing some computer hardware (cameras, microphones, screen sharing, hard drive access, etc) by default unless given permission. Users need to access the Security and Privacy control panel under the OS system preferences to grant this permission.
You may encounter one of the following error messages when you try to share the screen for the first time in Zoom.
To enable screen sharing, open the System Preferences control panel. This can also be accessed through the Apple menu at the top, left on the desktop screen.
Navigate to the panel for “Security & Privacy”.
Navigate to the “Privacy” tab and scroll down to the “Screen Recording” selection located in the left-hand list. This list is also used to give applications permission to access cameras, microphones, local files, and other devices as necessary.
NOTE: You may need to unlock the panel (click the closed padlock below the list and enter your computer password) to make changes if the selections are greyed out.
Once “Screen Recording is selected, ensure that zoom.us.app is listed and has a checkmark next to it in the right-hand box. You can add Zoom to the list manually by clicking the (+) button below and navigating to the Zoom application on your computer.
If you currently have the Zoom app open, it will prompt you to close it and reopen/rejoin the meeting in order to make these changes.
Once the Zoom application is reopened, screen sharing will be available on the machine.