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Open your Dropbox folder. Press Ctrl and click the folder you want to share. Click Share. Enter the email address(es) of those you want to invite. Choose a sharing method. Stop sharing a file.

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You'll see it on the left side of Finder. Choose the method that best suits your needs: Can edit: Allows the person you're sharing with to add, edit, and delete files. Can view: Allows the person to view the contents of the folder but not make any changes. To make your file or folder private again: Press Ctrl as you click the shared file or folder, then select Manage Access. Click the dropdown next to the name of the person with whom you've shared the file. If you're sharing with more than one person, you'll need to do this for each person. Click Remove.