Data Recovery Case File · Second Fixes & Trade Handoffs · The Split Is the Clue
One Volume Reading and Another Not Points at Where, Not Whether
This trade enquiry reports a partial result with a useful shape. A customer's drive suspected of head damage, mounted externally, where "it can see the system volume but not the data partition." That split is a good deal more informative than a drive that shows nothing — the device works, and the difficulty is confined to particular regions rather than spread across the whole of it.
| Media | 1TB hard drive mounted externally for recovery — system volume presenting normally, data volume not accessible; head damage suspected by the submitting technician |
| Reported situation | Customer drive suspected of head damage · drive mounted on an external adapter · system volume visible and readable · data volume not presenting · recovery of user documents and files sought · submitted through a trade intermediary |
| Fault class | Localised read failure affecting specific regions — enumeration and partial volume access retained; damage confined rather than general |
| Equipment used | Partial volume access interpreted as regional read failure rather than device failure · imaged write-blocked under strict per-sector timeouts with readable regions taken first · marginal regions revisited across later passes · data volume structures located from duplicate records · recovered content validated by opening |
The decode: why the split matters, and what it says about extent
What the visible volume already proves: a great deal. The drive powers, reaches speed, identifies itself, and returns data well enough for a volume to be read and mounted — every stage of the chain works, which a drive with a general fault could not manage.
Why the invisible one is therefore not a device question: the same drive is doing both. If it can read one volume it can read in principle, so the failure to present the other is about particular regions rather than about the drive's ability to function.
Why partitions occupy distinct physical areas: volumes are laid out in sequence across the platters. A system volume typically sits at the start and a data volume after it, which means they are physically separated — and localised damage can affect one while leaving the other entirely readable.
What that suggests about the suspected head damage: it fits, with a qualification. A damaged head reads some surfaces or regions and not others, and on a multi-platter drive one failing head affects the areas it is responsible for while the rest continue normally.
Why that is consistent with the pattern rather than merely compatible with it: a head that had failed completely would produce far more than one missing volume. Losing exactly one region while another reads cleanly is what partial head involvement looks like.
What specifically is likely to be unreadable: not necessarily the whole volume. A volume fails to present when the structures at its beginning cannot be read, and those occupy a small area — so the bulk of the data volume may be perfectly readable behind an unreadable few sectors.
Why that possibility is worth stating clearly: it separates a missing volume from missing data. The volume is absent because its description could not be read, and the content it described may be entirely intact — which is a considerably better position than the symptom suggests.
What is done rather than retrying: the drive is imaged under strict per-sector timeouts, so a difficult region is deferred rather than allowed to absorb the available time. Readable areas are captured first, and the marginal ones revisited across later passes — a region that fails on one attempt frequently returns on another.
How the missing volume is then recovered: from the image, using the duplicate structures filesystems keep elsewhere. The description of the volume is rebuilt from its own internal records rather than from the unreadable original.
What must not happen: no attempts to repair or rebuild the partition on the original drive. Everything is done from the image once it exists.
On the bench
Partial volume access was interpreted as regional read failure rather than device failure — a readable volume establishing power, rotation, identification and data return as functional, so failure to present another volume concerns specific regions, volumes occupying distinct physical areas laid out in sequence. A volume fails to present when the structures at its beginning are unreadable, which occupy a small area and may sit ahead of entirely readable content. Imaging ran write-blocked under strict per-sector timeouts with marginal regions revisited across passes.
The outcome
Partial access read as regional failure, the drive imaged under capped timeouts with readable regions first, and the missing volume rebuilt from duplicate records. Free assessment, one fixed written figure including VAT; where a drive has to be opened, 50% of parts and labour is payable upfront with the balance only on success — otherwise no recovery, no fee. The decode: one volume reading proves the drive works, so the other missing one is about regions rather than the device. And a volume disappears when the small structure at its start cannot be read — the content behind it may be entirely intact.
When one volume reads and another does not
Read that split as good news rather than partial failure. A volume mounting normally proves the drive powers, reaches speed, identifies itself and returns data — the whole chain works — so the missing volume is a question of specific regions rather than the device. Volumes occupy distinct physical areas laid out in sequence, so localised damage can take one while leaving the other untouched. Note too that a volume disappears when the small structure at its beginning is unreadable, and the bulk of its content may sit behind that entirely intact. Don't attempt to repair or rebuild the partition on the original.
That narrows it usefully — call Easy Data Recovery on 028 9002 0144; partial access read as regional failure, imaged under capped timeouts with readable regions first, missing volume rebuilt from duplicate records.
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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.