Prepare Your PC for BitLocker

Using Microsoft's BitLocker Drive Preparation Tool

In order for a computer encrypted with BitLocker to be able to boot, core operating system files must be stored in a separate, unencrypted volume. It doesn't need to occupy much space- only 1.5 Gb. But, if the PC was not configured and installed with BitLocker in mind, there is a very good chance that it is not properly partitioned for BitLocker. Thankfully, Microsoft developed a tool, the BitLocker Drive Preparation Tool, which automates the process of repartitioning the hard drive to get it ready for BitLocker encryption.

Let me start with one significant caveat- the BitLocker Drive Preparation Tool is only available for Windows Vista Ultimate and Windows Vista Enterprise editions (it also works with Windows Server 2008). Users of Windows Vista Home or Windows Vista Business editions will still have to find another tool or use old-fashioned methods for repartitioning the hard drive in preparation for BitLocker.

Aside from that caveat, there are also other system requirements to keep in mind before using the BitLocker Drive Preparation Tool. The excerpt below is from Microsoft's Description of the BitLocker Drive Preparation Tool:

System requirements To create a new partition or to merge unallocated space with an existing partition, the target system must meet the following requirements:

• A genuine version of Windows Vista Ultimate, Windows Vista Enterprise, Windows Vista Ultimate Service Pack 1, Windows Vista Enterprise Service Pack 1, or Windows Server 2008 must be installed.
• The active partition must contain boot configuration data and boot files.
• The target partition must meet the following requirements: • The partition must be on a simple disk that is initialized for basic storage.
• The partition must be a primary partition. Extended drives and logical drives are not supported.
• The partition must be formatted by using the NTFS file system.
• The partition must not be compressed.
• The cluster size of the partition must be less than 4 KB or equal to 4 KB.
• The partition is not using software spanning, software mirroring, or software RAID. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
  • 314343 (http://support.microsoft.com/kb/314343/) Basic storage versus dynamic storage in Windows XP
  Note This tool works correctly in hardware RAID configurations.
• For a split operation, at least 10 percent of the active partition must remain free after the partition size is reduced by 1.5 gigabytes (GB).
• For a merge operation, the partition's total capacity must be at least 1.5 GB. Also, the partition must have at least 800 MB of free disk space.

To begin with, you need the tool. You can get the tool from this Microsoft site.

Once you have the tool installed, you need to start it up by doing the following:

1. Click Start
2. Select All Programs
3. Click Accessories
4. Choose System Tools
5. Click BitLocker
6. Select BitLocker Drive Preparation Tool

Once the tool is initiated, it will do the following:

• Create the second volume that BitLocker requires
• Migrate the boot files to the new volume
• Make the volume an active volume

Once the BitLocker Drive Preparation Tool is completed, you have to restart Windows for the changes to take effect. After you restart the computer, the drive will be configured correctly for BitLocker.