How to use "Used Disk Space Only" encryption in Windows 7

Question

I'd like to know if Bitlocker's "Encrypt Used Space Only" feature in Windows 7 can be tuned to speed up the encryption process, for instance by tweaking the registry or adding services or packages. Is this possible?

Answer 1

As far as I know this was only added in Windows 8 BitLocker, but feel free to check for it on Windows 7. You need to edit Group Policy at Computer Configuration → Administrative Templates → BitLocker Drive Encryption → Operating System Drive → Enforce Drive Encryption type on Operating System Drive. The options are:

• Allow User to Choose
• Full Encryption
• Used Space Encryption

This GPO is also available for Fixed Data Drives and Removable Drives.

Keep in mind it is recommended to always do full encryption.