Externals — the bridge board
Fails at least as often as the disk behind it. The drive is healthy and nothing can reach it. Send the complete unit.
Very common
Hardware encryption living on the enclosure rather than the disk, shingled recording in drives that were never labelled as such, and sealed helium units that cannot be opened conventionally. Each changes what is possible and what you should avoid.
WD puts hardware encryption in the USB bridge and runs it by default, with no password ever set. Nothing reveals this until the disk is separated from the board holding its key — and the board looks like packaging.
The most consequential and the most commonly self-inflicted.
Most modern My Passport and My Book units encrypt their contents in hardware whether or not anyone set a password. The encryption is performed by the small USB bridge board inside the enclosure, and the key material lives on that board — not on the disk.
So removing the drive and connecting it directly, which is standard practice on many other brands, presents a disk full of ciphertext. Windows reads it as unformatted and offers to initialise it, and accepting damages a drive that was perfectly healthy. Worse, if the enclosure is then discarded, the only component capable of decrypting the contents has gone in the bin.
If you have already done it: keep the enclosure and the board and send both. Recovery is materially harder without it and sometimes impossible.
Present in a range of WD drives, and it changes both failure behaviour and recovery time.
Shingled magnetic recording overlaps adjacent tracks like roof tiles to increase density. Reading is unaffected. Writing is not: changing data in one track requires rewriting the tracks that overlap it, so the drive stages writes in a cache and reorganises them in the background afterwards.
Two consequences matter. Sustained writing — a large restore, or a RAID rebuild — can exhaust that cache, at which point throughput collapses dramatically and the drive may appear to have failed. This caused real problems when SMR drives were used in NAS arrays, and WD faced significant criticism in 2020 for shipping SMR in Red drives marketed for exactly that use without disclosing it.
For recovery, imaging an SMR drive is slower because the translation between logical addresses and physical tracks is more complex, and a drive with an interrupted background reorganisation may hold data in the cache that has not yet reached its final location.
Relevant on larger capacity units, and it affects who can work on them.
High-capacity WD and HGST drives are filled with helium and hermetically sealed. Helium is less dense than air, so the heads fly with less turbulence and more platters fit in the same height — which is how 14TB and above became practical.
The seal is the point. Once broken the helium escapes and cannot simply be replaced, so these cannot be opened on a standard clean-air bench and closed again. Work on them requires a controlled environment specifically for the purpose, and it is worth asking directly whether a firm can handle helium units before sending one.
Where the fault is electronic or firmware rather than mechanical, none of that applies — the drive never needs opening, and those are the commonest faults regardless of capacity.
Fails at least as often as the disk behind it. The drive is healthy and nothing can reach it. Send the complete unit.
Built for continuous operation, so failures tend to arrive as a degraded array nobody was monitoring rather than a single dead disk.
Spins normally, reports zero capacity or a blank model. The drive cannot describe itself; the data is untouched.
Clicking, grinding, seized bearings. Donor parts matched by family, firmware revision and head configuration — and a sealed helium unit needs specialist handling.
No. Most modern My Passport and My Book units encrypt in hardware with the key on the USB bridge board, so a bare disk reads as unformatted even when healthy — and Windows then offers to initialise it, which damages a working drive.
Recovery is harder and sometimes impossible, because the bridge board held the key material. If you still have the enclosure anywhere, retrieve it. Send it with the drive even if it appears damaged.
Shingled magnetic recording overlaps tracks to increase density, which makes sustained writing much slower once its cache fills. WD was criticised in 2020 for shipping SMR in Red drives marketed for NAS use without disclosing it — check the specific model number.
Yes, though mechanical work on them needs a controlled environment built for the purpose, since the seal cannot simply be broken and remade. Electronic and firmware faults do not require opening the drive at all.
Because the bridge board is doing more work than a simple adapter — interface translation and hardware encryption — and it is the component exposed to every knock, cable pull and power event.
From £300 plus VAT for a single drive or external, and from £500 plus VAT for NAS and array work, after a free 48-hour diagnostic. Send external units complete with their enclosure.