Acho que a resposta depende do software de recuperação de disco rígido que você usa. Steve Gibson, do Gibson Research Center, é pioneiro na recuperação de dados. Se você ler o website dele sobre o produto SpinRite, ele discutirá em profundidade como o software dele pode recuperar parcialmente os arquivos em que outros produtos não recuperarão um arquivo se um setor estiver ruim.
Aqui está um excerto de exemplo onde ele fala sobre a recuperação parcial de arquivos:
Accept Partial Data: If the Dynastat analysis is unable to perfectly
reconstruct the sector's data, it will at least be able to identify
the data bits that differed from one reading to the next. This allows
it to greatly minimize the uncertainty within the sector's damaged
area and to recover most of the sector's 4096 individual data bits.
SpinRite will log the name of the file whose sector was not completely
recovered and replace the file's completely unreadable sector (which
any other software would have simply discarded) with this "mostly
correct" now-readable sector so that all but a few data bits of the
file can still be read and used.
This is obviously a huge improvement over losing the entire file due
to one of its sectors being completely unreadable.
Aqui está uma em que acho que ele esclarece sua questão descrevendo um método usado:
Rather than giving up when a sector can't be read, or rather than
taking whatever data the drive might be willing to begrudgingly yield,
the DynaStat system accumulates a comprehensive statistical database
about the behavior of any troubled sector's data through the
accumulation and classification of up to 2,000 individual sector
rereads. By understanding the unlock/relock behavior of the drive's
data-to-flux-reversal encoder-decoder, and by processing the sector's
data "tails" after encountering a defect of any kind, the Dynastat
technology "reverse engineers" the sector's original data from the
statistical performance profile of the unreadable sector's flux
reversals. As a result, SpinRite can often completely recover data
that would otherwise have been utterly lost. Needless to say, no other
utility has ever incorporated such technology.
Você pode ler mais aqui:
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