Command option Sample:manage-bde -WipeFreeSpace

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manage-bde -WipeFreeSpace オプション

manage-bde -WipeFreeSpace command to transition the volume to full-volume encryption on these types of volumes. This is blocked in order to avoid expanding thinly provisioned volumes to occupy the entire backing store while wiping the unoccupied (free) space
    Protecting cluster shared volumes and storage area networks with BitLocker (Windows 10) | Microsoft Docs : http://docs.microsoft.com/en-us/windows/security/information-protection/bitlocker/protecting-cluster-shared-volumes-and-storage-area-networks-with-bitlocker

manage-bde のオプション一覧