Windows 11, Windows 10, and even older versions come pre-installed with a security and encryption feature called BitLocker. It enables users to encrypt everything on the drive where Windows is installed, protecting that data from theft or unauthorized access. If you haven’t heard of it, that’s because the feature isn’t available on every Windows PC. It is only available on the Windows Pro, Enterprise, and Education editions.

BitLocker not only encrypts the Windows drive but also external drives. Encrypting a removable drive, like a USB stick, is quicker and easier than encrypting the main Windows drive. Here, we will discuss how to do it all.

Before you get started

BitLocker is a useful but limited feature. It is only available on Windows 11 (and 10) Pro, Enterprise, and Education editions. It also only works with Windows devices, which means you have to use a Windows PC to encrypt your drive, and only Windows PCs can decrypt it. You will not be able to access your data on a non-Windows computer.

You can use BitLocker on most types of removable storage, like USB flash drives, SD cards, MicroSD cards, and external hard drives. As long as the storage uses NTFS, FAT16, FAT32, or exFAT file systems, it should work.

If you have partitioned an external drive, the partition you want to protect has to meet all the following criteria:

• It needs to be the active partition
• It cannot already be encrypted by something else
• It has to be at least 250MB in capacity

Encrypting an external drive using BitLocker

Encrypting a removable drive using BitLocker takes less than a minute. After the encryption process ends, each time you plug your device into a Windows computer, File Explorer shows the device with a lock icon, which signals that the device is encrypted. To access its content, you must enter the password set during the encryption process.

1. Plug in the USB drive or connect the hard drive you want to encrypt.
2. Open the Windows search bar, type "BitLocker," click on Manage BitLocker and open it.
3. Find your removable drive under Removable data drives – BitLocker To Go and select it.
4. Click Turn on BitLocker to start the encryption process (image shows what it looks like after turning it on). This may take a few minutes.
5. Choose Use a password to unlock the drive, type in a password, confirm it, and then click Next.

After setting the password, you’ll need to back up the recovery key. This key allows you to access the encrypted drive if you forget the password. You can save the key as a TXT file on your computer, store it on a USB drive, save it to your Microsoft account, or print it and keep it somewhere safe.

In the BitLocker Drive Encryption window, you will see a couple of options. If the USB drive or hard drive is new and does not have any files on it yet, go with Encrypt used disk space only. If the drive already has files and folders, it is better to choose Encrypt entire drive to make sure everything is protected.

Accessing an encrypted external drive

To access an encrypted external drive, connect it to your computer. When you plug it in, you might see a message saying 'Location is not available' or 'Access is denied.' This just means BitLocker is doing its job. Click OK, and then follow the steps below.

1. Open File Explorer.
2. Click This PC to see a list of your folders, devices, and drives.
3. Double-click the encrypted drive you want to unlock.
4. Enter the password for the drive and click Unlock.

If you no longer need to protect your removable drive with BitLocker To Go, you can remove the protection easily. Start by inserting the drive into your computer and unlocking it with your BitLocker password. In the BitLocker manager, locate your drive in the list and click Turn BitLocker off, then confirm the action when prompted.

Keep your external drives safe

BitLocker is one of the simplest ways to encrypt an external drive on Windows, as long as you're using it with Windows devices. It's just one of many security features in Windows 11. If you're interested in learning more, check out Smart App Control, a new feature introduced in Windows 11 version 22H2. And if you want to get the most out of BitLocker, here are 5 tips to use it more efficiently.