Windows 7 / Getting Started

TPM with PIN and External Key

In Windows 7 and Windows Vista SP1, you have an additional option for BitLocker security on computers with a TPM: requiring the user to type a PIN and insert a USB key. This provides the highest level of BitLocker protection by requiring something the user knows (the PIN) and something the user has (the external key). For an attacker to successfully access data on a BitLocker-protected partition, the attacker needs to acquire the computer with the hard disk, have the USB key, and work with the computer's owner to acquire the PIN.

You must use the Manage-bde.exe BitLocker command-line tool to configure this authentication option. Manage-bde.exe is discussed later in this section.

External Key (Require Startup USB Key At Every Startup)

The user provides the VMK on a USB flash drive or similar external storage so that BitLocker can decrypt the FVEK and the volume without requiring TPM hardware. The external key can be either the standard key or a recovery key created to replace a lost external key.

Using a startup key without TPM does allow you to encrypt a volume without upgrading your hardware. However, it does not provide boot integrity, and it will not detect whether the hard disk has been moved to a different computer.

Recovery Password

The user enters a 48-character recovery password, which decrypts the VMK, granting access to the FVEK and the volume. The recovery password is designed with checksums so that IT support can read the password to a user over the phone and easily detect whether a user has mistyped a character. For more information, read the section titled "How to Recover Data Protected by BitLocker" later in this tutorial.

Clear Key

No authentication occurs. BitLocker does not check the integrity of the computer or operating system, and the VMK is freely accessible, encrypted with a symmetric key stored in the clear on the hard disk. However, the volume remains, in fact, encrypted. This is used only when BitLocker is disabled (to upgrade the computer's BIOS, for example). When BitLocker is re-enabled, the clear key is removed and the VMK is rekeyed and re-encrypted. For more information, read the section titled "How to Disable or Remove BitLocker Drive Encryption" later in this tutorial.

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In this tutorial:

  1. Managing Disks and File Systems
  2. Overview of Partitioning Disks
  3. How to Choose Between MBR or GPT
  4. Converting from MBR to GPT Disks
  5. GPT Partitions
  6. Choosing Basic or Dynamic Disks
  7. Working with Volumes
  8. How to Create a Simple Volume
  9. How to Create a Spanned Volume
  10. How to Create a Striped Volume
  11. How to Resize a Volume
  12. How to Delete a Volume
  13. How to Create and Use a Virtual Hard Disk
  14. File System Fragmentation
  15. Backup And Restore
  16. How File Backups Work
  17. File and Folder Backup Structure
  18. How System Image Backups Work
  19. How to Start a System Image Backup from the Command Line
  20. How to Restore a System Image Backup
  21. System Image Backup Structure
  22. Best Practices for Computer Backups
  23. How to Manage Backup Using Group Policy Settings
  24. Previous Versions and Shadow Copies
  25. How to Manage Shadow Copies
  26. How to Restore a File with Previous Versions
  27. How to Configure Previous Versions with Group Policy Settings
  28. Windows ReadyBoost
  29. BitLocker Drive Encryption
  30. How BitLocker Encrypts Data
  31. How BitLocker Protects Data
  32. TPM with External Key (Require Startup USB Key At Every Startup)
  33. TPM with PIN (Require PIN At Every Startup)
  34. TPM with PIN and External Key
  35. BitLocker To Go
  36. BitLocker Phases
  37. Requirements for Protecting the System Volume with BitLocker
  38. How to Enable the Use of BitLocker on the System Volume on Computers Without TPM
  39. How to Enable BitLocker Encryption on System Volumes
  40. How to Enable BitLocker Encryption on Data Volumes
  41. How to Manage BitLocker Keys on a Local Computer
  42. How to Manage BitLocker from the Command Line
  43. How to Recover Data Protected by BitLocker
  44. How to Disable or Remove BitLocker Drive Encryption
  45. How to Decommission a BitLocker Drive Permanently
  46. How to Prepare AD DS for BitLocker
  47. How to Configure a Data Recovery Agent
  48. How to Manage BitLocker with Group Policy
  49. The Costs of BitLocker
  50. Windows 7 Encrypting File System
  51. How to Export Personal Certificates
  52. How to Import Personal Certificates
  53. How to Grant Users Access to an Encrypted File
  54. Symbolic Links
  55. How to Create Symbolic Links
  56. How to Create Relative or Absolute Symbolic Links
  57. How to Create Symbolic Links to Shared Folders
  58. How to Use Hard Links
  59. Disk Quotas
  60. How to Configure Disk Quotas on a Single Computer
  61. How to Configure Disk Quotas from a Command Prompt
  62. How to Configure Disk Quotas by Using Group Policy Settings
  63. Disk Tools
  64. EFSDump
  65. SDelete
  66. Streams
  67. Sync
  68. MoveFile and PendMoves