MacOS Big Sur black screen when screen sharing

Last Updated: December 15, 2021

It is possible that you might experience a black screen when trying to share files with others in a meeting or webinar when using Zoom for MacOS. If these factors are combined with a device that is updated to the Apple Big Sur OS and you are using a wired connection for your internet connection, it is possible to experience a black screen. The UDP protocol may not be able to transfer packets whose size exceeds a certain threshold on macOS Big Sur.

Issue resolution

Apple is working on a fix for this issue, which will appear in the next update to MacOS, but in the meantime, we recommend you utilize the wireless connection instead of relying on the wired connection. Changing the Zoom screen share settings to use a TCP connection is the best solution if you need a wired connection with your device.

• Sign into the Zoom desktop client by using your email address and password.
• Go to the Settings tab by clicking your profile picture.

• Select the option to Share Screen from the dropdown menu.
• Choose Advanced from the dropdown menu.
• Check the box that says Use TCP connections to share screens.