BitLocker Drive Encryption in Windows 7

The BitLocker Drive Encryption helps you to protect all files stored on the Operating System Drive, on fixed data drives or on removable data drives (such as external hard drives or USB flash drives).

BitLocker encrypts the entire drive. All the Windows system files necessary for startup and logon are also encrypted. You can log on and work with your files normally, but BitLocker can help block hackers from accessing the system files.

When you add new files to a drive that is encrypted with BitLocker, BitLocker encrypts them automatically. If you share encrypted files on the network then they can be normally accessed by the authorized users only.

Hardware requirements for BitLocker Drive Encryption

To use BitLocker Drive Encryption, your computer has to meet certain hardware requirements. These requirements vary depending on the type of drive that you are encrypting.

Hardware requirements for the drive that Windows is installed on

To encrypt the drive that Windows is installed on (the operating system drive), BitLocker stores its own encryption and decryption key in a hardware device that is separate from your hard disk i.e. either Trusted Platform Module (TPM) or a removable USB Flash Drive.
To turn on BitLocker Drive Encryption on the operating system drive, your computer’s hard disk must:

Have at least two partitions. One partition must include the drive Windows is installed on and must be at least 400 MB. This is the drive that BitLocker will encrypt. The other partition is the active partition, which must remain unencrypted so that the computer can be started. If your computer does not have two partitions, BitLocker will create them for you.

Hardware requirements for data drives

You can use BitLocker to encrypt fixed data drives (such as internal hard drives) and removable data drives (such as external hard drives and USB flash drives). To encrypt a data drive, it must be formatted using either the exFAT, FAT16, FAT32, or NTFS file system and must be at least 128 MB.

Steps to Turn On/Off BitLocker:
1. Click the Start button to view the Start Menu and then choose the Control Panel option.

2. The Control Panel window opens up.

Now click the System and Security link from this window.

3. The System and Security section of Control Panel opens up and you can see the direct link for the BitLocker Drive Encryption.

4. Click on the BitLocker Drive Encryption and a new window opens up.

By default the BitLocker Drive Encryption is Off for the Hard Disk Drive.

5. Click Turn On BitLocker. If a compatible Trusted Platform Module
(TPM) security device is not present on your computer the window will look like below:

Note: To use BitLocker Drive Encryption, your computer has to meet certain hardware requirements.

Otherwise, this opens the BitLocker setup wizard. Follow the instructions in the wizard. If you are prompted for an administrator password or confirmation, type the password or provide confirmation.


6. Click Turn Off BitLocker. This opens the BitLocker Drive Encryption dialog box. If you are prompted for an administrator password or confirmation, type the password or provide confirmation.

To decrypt the drive, click Decrypt the volume. To temporarily suspend BitLocker, click Suspend BitLocker Drive Encryption.