How Should I Password Protect an External Drive?

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I’m wondering if it’s possible to password protect a USB flash drive or any other external hard drive if I’m using Windows as my operating system? In Windows, there’s a feature called ‘Bitlocker’. Is it any different than putting on a password?

BitLocker is one solution, and it’s much more than “just” password protecting the drive.

What you’re really looking for is encryption.

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A password alone is not enough

The reason you’re looking for encryption is that a password by itself isn’t enough.

For example, let’s say you somehow attach a password to a drive1. Now someone steals your computer, or gains access to that computer using some other operating system or technology that simply ignores the password requirement. Or perhaps they perform some kind of forensic data recovery on the drive. Either way, they can bypass the password and access your files.

That’s not much protection.

What you want instead is that the data you care about — everything on the drive, in your example — be encrypted, so regardless of how it might be accessed, the data is inaccessible without your password.

Approach #1: BitLocker

Included in Windows 7 and later, in all editions except “Home,” “Starter” or Windows 7’s “Pro”, BitLocker is a whole-drive encryption technology that can be used on external or internal drives.

Setting a Password in Bitlocker

Windows will encrypt the drive for you, and require the password you set to access that drive’s contents in the future. (When given the opportunity to save a recovery key, do so. That way, even if you forget the password, you’ll be able to regain access. Without the password or recovery key, the data is completely inaccessible.)

This is the kind of protection you’re looking for.

The only real “problem” that remains is that your drive can only be used with Windows, and with Windows editions that support BitLocker. The drive cannot be viewed elsewhere.

Option #2a: VeraCrypt whole-drive encryption

VeraCrypt, the heir-apparent to the long-favored TrueCrypt, is a high-quality encryption program that supports everything we need: encrypting the entire disk, like BitLocker, and requiring a password, also like BitLocker.

The difference is that it’s from a third party, works on any edition of Windows (include Home), and is compatible with other systems, including Mac and Linux.

VeraCrypt Password Choice

Once you encrypt a drive, you “mount” it to access its contents, providing the password to do so.

There is no “recovery key” for VeraCrypt encrypted drives, so make sure your data is backed up and that you never lose the password you used to encrypt the drive.

When you encrypt a drive, the entire drive is encrypted, and you need the password to access any files (or folders) anywhere on that drive.

An Encrypted Drive

Option #2b: VeraCrypt volume encryption

A hybrid approach avoids encrypting the entire drive, but instead creates a single (large-ish) file, which is then encrypted and used as a container for your files.

Encrypted File Container

Rather then mounting the drive, you mount that encrypted container, specifying the password, at which point its contents become visible as if it were a separate drive. You can choose to place unencrypted data in the drive directly (accessed as E: in the diagram above), or deal with data that’s encrypted in the mounted file container (accessed in drive F: in the diagram above).

As long as the container is mounted and password provided, its contents are available as on any drive. Once unmounted, the files are no longer visible.

VeraCrypt encrypted containers have the advantage that the container itself can be copied to other drives or devices — even using other operating systems — and mounted there for access, when the password is supplied.

My preference

I tend to use BitLocker for drives that are permanently mounted in the computer, such as the system drive. Of course, if you have Windows Home Edition, that’s not an option, in which case VeraCrypt would be my choice.

If I want encryption on an external drive, I use VeraCrypt — either whole-drive or container — because this gives me the flexibility of using that drive or container in any of my systems, whether Windows, Mac, or Linux.

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Using Bitlocker on an External Flash Drive   Using Bitlocker on an External Flash Drive

Footnotes & references

1: Technically not possible in Windows.

27 comments on “How Should I Password Protect an External Drive?”

  1. Totally agree with Leo: Truecrypt is the way to go. I’ve used for years and it works well. As Leo says, the portability is important.
    I am all for security but I always have an eye on “What To Do When I Die”! Sounds morbid but you should consider this when encrypting your valuable data: if it will be valuable to others that you care about after you die – how do they get to it if you have encrypted. With Truecrypt you can leave your password without fear of the account being closed.

  2. Right now I’m using a Linux Mint box connected to a portable hard drive that I encrypted with Truecrypt using a Win 7 machine. Truecrypt is totally the way to go.

  3. One other caveat with TrueCrypt is that you need to run it from an account with Administrator rights on the computer you’re running it from.

    • It REALLY depends on the implementation, but yes – when done properly, in a way that works with your OS, a self-encrypting drive is just as good. I tend to prefer software solutions, since I feel like I have more control, but that’s a minor point I think.

  4. When I saw the title of this article, I was excited thinking that it would give me a way to protect my external drive from ransomware. Unfortunately, for reasons that are unavoidable, I have to leave this drive always attached to my computer, making it vulnerable to any ransomware that decided to encrypt this USB external drive. Again, unfortunately, this is the drive that also contains my image backup, so any ransomware encryption would make my image backup worthless.

    In the case of ransomware, any pre-encryption of my external drive wouldn’t help as the malware would encrypt it again with its own key anyway making it unreadable to me.

    I was hoping that there might be a simple way to password protect the external drive from ransomware attacks, rather than from physical attacks as mentioned in this article. Basically, I want to keep the ransomware from accessing my backup USB drive somehow.

    Any ideas?

  5. @Thomas Tomaszewski
    Caveat: I use Linux, so may be different in Windows. I just did a full volume encryption on a USB stick with Veracrypt. On Linux, the stick will not mount unless you first open Veracrypt and enter the password. Once the password is accepted the stick mounts normally. This says to me that the stick (or a USB disk drive) can be left connected to the system but unmounted until you need to use it. Malware (ransomware) could not access as long as the device isn’t mounted. My problem is this: I use my external HD to do a monthly offline (boot from a CD) bare metal backup. Since Veracrypt isn’t running when the system boots to a CD there’s no way to access the disk to do the backup. Should be no problem doing any backups when Linux is running however, so my daily file backups should work as long as I make sure the disk is mounted before and dismounted after.

    • An addendum to my previous post. I think the entire external volume would have to be encrypted. If you just use an encrypted “Container” file then the disk drive could seemingly be mounted by malware without a password and then the encrypted container is just another file on the disk drive to be encrypted by the malware. If the entire drive is encrypted then the password is required to mount it.

  6. Don’t currently encrypt. But with so much going on these days with ransomeware maybe I should. I live in an area where I feel pretty safe with my always-at-home laptop. And when I am not using my external hard drive(s), these are physically dismounted. So I presume they could not be held hostage (unless there is ransomeware that could activate when I physically mount them again?!).

    But do I understand that some ransomeware, etc. could infect my mounted external drives, even with these being password protected? If so, how?

      • Since BitLocker is not for Windows 7 Professional, is this of some help, even though it is just at the file level?:

        What is Encrypting File System (EFS)?
        Encrypting File System (EFS) is a feature of Windows that you can use to store information on your hard disk in an encrypted format. Encryption is the strongest protection that Windows provides to help you keep your information secure.

        Some key features of EFS:

        * Encrypting is simple; just select a check box in the file or folder’s properties to turn it on.
        * You have control over who can read the files.
        * Files are encrypted when you close them, but are automatically ready to use when you open them.
        * If you change your mind about encrypting a file, clear the check box in the file’s properties.

        Note
        EFS is not fully supported on Windows 7 Starter, Windows 7 Home Basic, and Windows 7 Home Premium. For those editions of Windows, if you have the encryption key or certificate, you can do the following:

        * Decrypt files by running Cipher.exe in the Command Prompt window (advanced users)
        * Modify an encrypted file
        * Copy an encrypted file as decrypted to a hard disk on your computer
        * Import EFS certificates and keys
        * Back up EFS certificates and keys by running Cipher.exe in the Command Prompt window (advanced users)

  7. Does taking a non-system disk offline using Windows Disk manager give any extra protection against malware or ransomware?

    • It depends on the malware software and how much effort its programmer put into it. Remember that a malware, especially ransomware, is software written by a very knowledgeable programmer. It can easily get into the Registry and do anything it wants (and it does), including mounting all “hidden” drives and then attacking them. But hiding drives in Disk Manager is additional protection against the lazy malware programmer. If you’re doing that, remember to also hide your system recovery partition.

    • It should yes, for most ransomware. While it’s POSSIBLE that ransomware could be written that deals with it, I’m not aware of any that would.

      • One thing to remember, if the malware just wants to destroy your data without demanding a ransom (I suppose it’s possible) then any drive that’s connected to the system can be foermatted whether it’s encrypted or not.

  8. Not having used VeraCrypt before, I’m wondering how often you have to enter the Password. If you make it a real long one, and you have to enter it whenever you save a file, that’d be a pain. So is it only when you first boot up?

    • You log in with a password to Veracrypt which mounts the volume as a logical drive. It stays mounted and open for reading and writing until Veracrypt is closed.

    • You only have to enter the password once. The encrypted container will be accessible as long as you don’t reboot or dismount the container. Just have your password manager generate a strong password, then save it in a secure note (that’s for Lastpass… I’m sure you can do it in any PW manager). When you want to open the encrypted container, just bring up the secure note in password mgr and copy/paste the password. For safety, though, write the password down and put it in a safe place.

    • One thing to remember: any drive that’s connected to the system can be formatted whether it’s encrypted or not. If the malware is just designed to screw up your system it could format the encrypted drive just as easily as any other.

  9. “Included in Windows 7 and later, in all editions except “Home” or “Starter”. Unfortunately Bitlocker’s not available for Windows 7 Professional – only Ultimate & Enterprise. Too bad – it would be very useful in the office.

  10. I’ve used TrueCrypt and now VeraCrypt for years. Wonderful, but that’s only folders. I need to encrypt my entire 1TB EXT USB drive but the directions on VC are horrible! [great software, terrible help]

    I can’t find the steps. Yes, it’s known it can be done but does not explain how.
    Does one begin with an empty drive?
    Then run VC to that drive?
    Then move data to the drive and then, what? Close VC?
    Or…?
    I am confused

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