This policy setting configures the maximum age of a file share shadow copy. File share shadow copies that are older than this age will be deleted by the File Share Shadow Copy Agent. Both the exposed shadow copy share and the corresponding volume shadow copy will be deleted.If you enable this policy setting the value specified determines the maximum age of a file share shadow copy.If you disable or do not configure this policy setting file share shadow copies older than 24 hours will be deleted.
System\File Share Shadow Copy Agent
At least Windows Server 2012 Windows 8 or Windows RT