In Device To Cloud Backup you may see a warning that you have backed up EFS files, you need to have the encryption key backed up to safely restore these files.

You can find it by going to the restore process on the users device (This can only be done on the desktop client not the web client).
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> Select the restore option on Backup Intelligence.
> Click next at the storage vault selection.
> At the protected item page click the search function at the top right of the window.
> Click on the drop down with "Name" and select "Type".
> At the "file drop down select "Windows EFS-encrypted file".
> Click "Search" at the top right of the window.
> It should then display the encrypted files/folders.