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Should you forget or lose your Surface Pro, a file saved in its Documents folder will be accessible in your OneDrive folder - either from your primary PC, or via the Office 365 web portal (See Signing in to Office 365 Online /wiki/spaces/FAQSTAGE/pages/24379647)
How secure is saving files on the Surface Pro?
Each Surface Pro is BitLocker encrypted. See BitLocker - User Guide
Data stored in OneDrive is considered appropriate for the majority of data produced by the University. See Security Guidance for Microsoft OneDrive for Business