Microsoft first introduced BitLocker drive encryption with Windows Vista back in 2007, though it was initially limited to the Enterprise and Ultimate editions. Over the years, it evolved into a core security feature of Windows. With Windows 11, Microsoft went a step further — BitLocker now activates automatically when users sign in with a Microsoft account during the setup process (OOBE). While this auto-encryption aims to secure user data, it has also caused some serious unintended consequences.
That’s exactly what happened to one unfortunate Reddit user, u/Toast_Soup (referred to as “Soup”), who ended up losing access to their data after a Windows reinstall.
Soup noticed their PC was lagging and decided to perform a clean installation of Windows. Their system had six drives — including the boot drive and two large backup drives (D: and E:), each with around 3TB of data. But once the reinstall was complete, those two drives appeared to have vanished. They were locked by BitLocker encryption, despite Soup never manually turning the feature on.
Unaware that Windows 11 automatically encrypts drives linked to a Microsoft account, Soup didn’t have the necessary BitLocker recovery keys — keys they didn’t even know existed. Without them, the data became permanently inaccessible. Even professional data recovery software couldn’t help, since BitLocker’s encryption is designed to prevent unauthorized access.
Desperate, Soup reinstalled Windows again, only to face the same encryption prompt — this time for the boot drive. Thankfully, they noted down the new recovery key and regained access to Windows. Unfortunately, their D: and E: drives remained permanently locked. When Reddit users suggested checking Microsoft account settings, Soup confirmed that only the key for the main C: drive was listed there.
What makes this situation worse is that BitLocker doesn’t just risk unexpected data lockouts — it can also impact system performance. Previous testing has shown that the software-based version of BitLocker can reduce SSD read/write speeds by up to 45%, as the CPU must continuously encrypt and decrypt data. This slowdown could explain the lag Soup noticed before resetting their system.
It’s worth noting that hardware-based encryption (known as OPAL) performs much better but isn’t what Windows 11 enables automatically. Some users in the Reddit thread also mentioned that even small system changes — like altering boot order — can unexpectedly trigger BitLocker on Windows 11 Home, even with a local account.
Windows 10 doesn’t exhibit the same automatic encryption behavior, nor does upgrading from Windows 10 to 11. Unfortunately, in Soup’s case, there’s little left to do other than wipe the drives and start over.
To avoid similar disasters, users should check BitLocker settings immediately after setup, disable automatic encryption if desired, and securely back up recovery keys. Always maintain external backups of crucial data — because once BitLocker takes over without your knowledge, recovery may not be possible.
