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If you're on a Mac and receive a message about not having permission to share your screen, switch to Safari and you'll be able to give the site permission.you can go to Self Service by clicking on the CNU sails at the top of your screen and choosing Self Service.
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In the box that pops up, you'll see Reset Google Screen Capture. Click the Run Now button under it.
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When you're done sharing, click the Present Now button again and choose Stop presenting.
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