To restart the OneDrive sync client on Windows 10, use these steps: but it's uploading and downloading files really slowly, then the software. The folder containing the files was online only (as per the "on demand" option in OneDrive), so, all files needed to be downloaded to the local HD. So I started uploading all my pictures, camera roll, word files, for wife and her OneDrive (~10GB) downloaded just fine in couple of hours.
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