Data Recovery Case File · Encryption · The Interrupted Conversion

Half plaintext, half cipher, all stranded: a BitLocker decryption that stalled on a drive that was failing all along

The decision that doomed this drive was made for a sensible-sounding reason. His encrypted 1TB WD Elements had grown tediously slow to unlock on an old PC, so the owner set BitLocker to decrypt it permanently — a routine operation, on healthy hardware. Hours in, the conversion stalled and stopped. Afterwards, Windows no longer detected the drive at all, BitLocker's own management wouldn't open with it connected, and — the detail that reframed everything — plugging it into his new PC effectively froze that machine until the drive was removed.

The enquiry

“I used Windows to encrypt it and it worked normally for months. It was taking too long to open with the password, so I decided to decrypt it. The process started alright, but after a few hours it got stuck and then stopped. Now Windows no longer detects the drive, I can't open 'Manage BitLocker' with it connected — and whenever it's connected to my new PC, it seems to lock the whole computer until I remove it. The data is mostly personal, and important.”

The misread that started it — and the state it left behind

Reconstruct the story from the bench and the first symptom changes meaning entirely. The drive wasn't slow to unlock because it was encrypted; unlocking is quick arithmetic. It was slow because the drive was already failing — reads crawling, the password prompt merely the moment he noticed. Decryption, prescribed as the cure, was the harshest possible medicine for that patient: a full-drive conversion is a marathon that reads and rewrites every occupied sector, and hours into forcing a sick drive through it, the drive did what sick drives do under marathon load elsewhere in this archive — stalled into the state where it answers nothing and holds any host's storage bus hostage, which is exactly the whole-PC freeze he described. What the collapse left behind is the genuinely delicate part: a volume frozen mid-conversion — a moving frontier with plaintext on one side, ciphertext on the other, and BitLocker's own record of where the frontier stood as the only map. That map is why the strict rule of these cases exists: nothing may write, "repair" or resume against the original, because the conversion state is as much the data as the data is.

The recovery

First the hardware, on its own terms: behind the USB Stabilizer's power control, the drive was imaged the way bus-stalling patients are — in disciplined bursts, each stall answered with a hard power cycle rather than a hopeful wait, reads resuming precisely where they stopped, the territory map filling burst by burst until the image stood complete. Then the cryptography, entirely on the copy: the volume's metadata located and read for the conversion watermark, and — with the password he'd never lost — the decryption finished on the image, ciphertext beyond the frontier unlocked exactly as the stalled process would eventually have done, plaintext before it taken as found, the two halves meeting seamlessly at the recorded boundary. Passware Forensic and Data Extractor shared the heavy lifting; the reunified NTFS volume mounted whole, and his personal archive came out verified.

Outcome

Effectively complete recovery of a volume that existed, when it arrived, as two half-drives sharing one failing disk. The lesson generalises past BitLocker to every full-drive operation there is: encryption, decryption, defragmentation, cloning, repartitioning — none of them are safe prescriptions for a drive that has become slow, because slowness is the illness they'll be forced through. When a drive drags, the first move is a copy of what matters, made gently; the drive's future can be decided afterwards, from the safety of having one.

Our case files are drawn from genuine enquiries received by our laboratory over the past ten years, anonymised to protect client confidentiality. Each one describes the diagnostic and recovery procedure our engineers apply to that fault, using the equipment listed.