Following an upgrade, recent versions of macOS may prompt a user to setup iCloud Drive. Files that are migrated to iCloud Drive can be accessed from other Macs, iOS devices, or iCloud.com. While some may find this service beneficial, others might inadvertently migrate their Desktop and Documents folder to iCloud Drive causing confusion and "lost" files. In the screenshot below, during setup assistant, leaving the check box ticked is what forces the Desktop and Documents folders to be moved to iCloud Drive.
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- Go to System Preferences through the Apple menu or dock icon.
- Click on the iCloud icon in System Preferences
- Click the "Options..." button Next to the iCloud Drive icon
- In here, uncheck the box to turn off "Desktop & Documents Folders"
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