What Is BitLocker? Windows Security Feature Overview
Learn how BitLocker full-disk encryption protects data on Windows devices and what you need to configure it safely.
BitLocker Overview
BitLocker is Microsoft’s full-disk encryption feature for Windows, designed to protect data if a device is lost, stolen, or decommissioned without proper wiping. When enabled, BitLocker encrypts the contents of a drive so that it cannot be read without the correct key or authentication method.
BitLocker is available on many editions of Windows, particularly Pro and Enterprise versions. It can be managed locally on individual machines or centrally via Active Directory, Microsoft Intune, or other management tools in business environments.
How BitLocker Protects Your Data
BitLocker uses strong encryption algorithms to scramble the data stored on a drive. During normal use, the decryption happens transparently after you authenticate at boot or unlock a removable drive. If someone removes the drive and tries to read it from another device, the data remains unreadable without the recovery key.
On systems with a Trusted Platform Module (TPM), BitLocker can verify that the boot process has not been tampered with before releasing the keys. Additional options include requiring a PIN, USB key, or both at startup for extra protection.
Deployment Considerations and Best Practices
Before enabling BitLocker, ensure you have a reliable way to store and retrieve recovery keys. In enterprise environments, keys are often backed up to Active Directory or Azure AD. For personal devices, Microsoft accounts or printed copies may be used, but they must be kept secure.
Plan for scenarios such as hardware failure, motherboard replacement, or forgotten PINs, all of which may require recovery keys. Combine BitLocker with strong account passwords and secure boot settings to create a robust line of defense against data theft from lost or stolen hardware.