Data Recovery Case File · Formatted & Logical Faults · It Did Not Stop
A Format Aimed at One Partition That Runs Through the Whole Drive Is a Different Loss
His enquiry describes an operation that exceeded its instruction. A drive returned from repair with one volume missing, where — believing the content mirrored to a cloud service — he "used the disk utility to format a smaller partition with a spare partition beyond," and "it continued to basic format the whole drive." The intended action was survivable and the actual one is broader, and the backup he relied on turns out to be partial.
| Media | Hard drive returned from prior repair with one volume absent — partition format initiated and extended across the entire device; content partially mirrored to a cloud service |
| Reported situation | Drive returned from a repair provider · one volume no longer present · content understood by the owner to be mirrored to a cloud service · format initiated against a single smaller partition · operation continuing across the whole drive · some partitions not fully backed up · optical media also held as partial backup |
| Fault class | Full-device format over multiple partitions — partition table and volume structures replaced with content regions largely retained; scope determined by which partitions lacked backup |
| Equipment used | Format scope established across the whole device before any recovery was scoped · backup coverage mapped per partition to narrow the target · imaged write-blocked at the block level before any interpretation · original partition boundaries recovered from residual volume structures · content carved by signature within each reconstructed partition |
The decode: what a basic format leaves, and where the real question lies
What a basic format does, which is the good news: very little. It writes fresh filesystem structures and marks the capacity available without erasing content, which is true whether it covers one partition or all of them.
Why running across the whole drive is nonetheless worse: it replaced the partition table too. The record of how the drive was divided is gone, so the boundaries of every volume have to be reconstructed rather than read.
Why that is recoverable: each volume left traces. Filesystem structures sit at predictable offsets within their own partitions, and finding them establishes where each began and ended.
Why the drive returning from repair with a volume already missing matters: two events have now occurred. Whatever the repair provider did preceded the format, and the missing volume may have been lost before he touched anything.
Why that changes what to expect: the missing volume's structures may already have been damaged. Reconstructing a partition that was intact until the format is easier than one that was already absent.
Now the part that governs the whole case: he acted because he believed the content was mirrored, and adds that some partitions are not fully backed up. The recovery is only needed for what the mirror does not hold.
Why establishing that first is the most valuable step: it defines the target. Comparing what the cloud service holds against what the drive held identifies exactly which partitions matter, and it costs nothing.
Why a mirror is so often partial without anyone noticing: synchronisation covers selected folders. A service mirroring a user's documents does not mirror other partitions, application data or archives, and the gap is invisible until it is needed.
Why his optical discs are worth cataloguing too: they are a second partial source. Between the mirror and the discs, the genuinely unique material may be a small fraction of the drive.
What must not happen now: nothing further written, and no attempt to recreate the partitions manually. Creating a partition writes structures where the originals are being read from.
On the bench
Format scope was established across the whole device before any recovery was scoped — a basic format writing fresh structures and marking capacity available without erasing content, but an operation extending across the device also replacing the partition table, so volume boundaries require reconstruction rather than reading. Filesystem structures at predictable offsets within each partition establish those boundaries. Backup coverage was mapped per partition to narrow the target.
The outcome
Format scope established across the device, backup coverage mapped per partition, and original boundaries recovered from residual volume structures. 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: a basic format writes structures and does not erase content, even across a whole drive. What it took is the record of how the drive was divided — and the boundaries can be found again.
A format that ran further than you intended
Stop using the drive and don't recreate the partitions manually, since creating one writes structures exactly where the originals are being read from. Take some reassurance: a basic format writes fresh structures and marks space available without erasing content, so what's actually lost is the record of how the drive was divided, and that can be reconstructed from traces each volume left. Then map what your cloud mirror actually covers — synchronisation usually covers selected folders only, so the genuinely unique material may be a small fraction.
Stop using the drive — call Cambridge Data Recovery on 01223 655015; format scope established first, backup coverage mapped per partition, original boundaries recovered from residual structures.
Request a quote online →
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.