Learn about Onedrive Files On-Demand
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With OneDrive Files On-Demand, you can:
Save space on your device by making files online only
Set files and folders to be always available locally on your device
See important information about files, such as whether they are shared
See thumbnails of over 270 different file types even if you don’t have the required application installed to open it
Right-click on the Onedrive Blue Cloud and select the Settings menu and then the Settings tab, and check the "Files On-Demand" checkbox "Save space and download files as you use them"