UnbitBitLocker To Go on Mac: open a Windows-encrypted USB flash drive
BitLocker To Go is the part of BitLocker that Windows uses for removable drives such as USB flash drives. Someone encrypted a stick on a Windows PC, and now you need the files on your Mac. macOS can’t unlock these drives by itself, but Unbit can open them read-only. Here is how BitLocker To Go works and what to expect on a Mac.
What BitLocker To Go is
BitLocker is Microsoft’s drive encryption for Windows. BitLocker To Go is the name for the same protection on removable drives: USB flash drives and external drives. In Windows you switch it on from File Explorer, choose how the drive unlocks – usually a password – and save a 48-digit recovery key.
A protected drive shows a padlock in Windows File Explorer, and Windows asks for the password when you plug it in. Everything on the drive is encrypted, not just a few folders.
What happens when you plug it into a Mac
macOS sees a disk it can’t read. It usually shows “The disk you inserted was not readable by this computer”, or the drive doesn’t appear in Finder at all. The files are intact: click Ignore, and never choose Initialize or Erase.
If the stick unlocks automatically on your own PC, that setting only applies to that PC. On a Mac you still need the password or the recovery key.
Open a BitLocker To Go drive with Unbit
- Install Unbit from its website and open it from the menu bar. The first launch shows where to enable Full Disk Access.
- Plug in the USB stick. Unbit finds it automatically and lists it under Drives.
- Enter the password you chose in Windows, then choose Open Drive. If you only have the recovery key, use that instead – see BitLocker recovery key on Mac.
- Choose Show in Finder and copy the files you need to your Mac.
- Choose Eject Safely before you pull the stick out.
The full walkthrough, with screenshots, is in How to open a BitLocker drive on a Mac.
Moving files between a Windows PC and a Mac
Unbit reads BitLocker To Go drives; it doesn’t write to them. That affects how you share files:
- Windows to Mac: put the files on the stick in Windows, then copy them off on the Mac.
- Mac to Windows: you can’t save onto the encrypted stick from the Mac. Use another route, such as a second drive formatted as exFAT (macOS and Windows both read and write it) or a cloud or network share.
- Sensitive files: an unencrypted exFAT drive is convenient but unprotected if it’s lost, so keep private data on the BitLocker stick and use it read-only on the Mac.
Things to know about USB sticks
- Plug the stick straight into the Mac rather than into an unpowered hub, and try another port if it isn’t listed.
- If the stick has several partitions, choose the one that is BitLocker-encrypted.
- Unbit supports drives encrypted on Windows 7 or later. The file system inside should be exFAT, FAT32 or NTFS.
- A memory card in a USB card reader normally appears to the Mac as an external drive, so it works the same way.
- If Windows is still encrypting or decrypting the stick, let it finish first.
More on drive types: Open a BitLocker SSD, HDD or USB stick on Mac.
Frequently asked questions
Is BitLocker To Go different from BitLocker?
It is the same technology. BitLocker To Go is simply the name used for removable drives such as USB sticks.
Can a Mac open BitLocker To Go without extra software?
No. macOS has no built-in BitLocker support, so you need a reader such as Unbit or a Windows PC.
Can I save files onto the stick from my Mac?
Not with Unbit, which is read-only by design. Copy files off the stick on the Mac and use Windows when you need to add or change files on it.
Will the stick still work on Windows afterwards?
Yes. Unbit only reads the stick and never changes it.
I have a recovery key but no password. Can I still open it?
Yes. Unbit accepts the 48-digit recovery key instead of the password. See BitLocker recovery key on Mac.
Does Unbit store my password?
Only if you tick “Remember this drive on this Mac”. It is then stored encrypted in your macOS keychain, and you can forget it at any time.