This setting lets you suppress the Restore button in the previous versions property page when the user has selected a previous version of a local file.
If this setting is enabled, then the Restore button will be disabled when the user selects a previous version corresponding to a local file.
If this setting is disabled, then the Restore button will remain active for a previous version corresponding to a local file. If the user clicks the Restore button, then Windows will attempt to restore the file from the local disk.
If this setting is not configured, it will default to disabled - the Restore button will be active when the previous version is of a local file.