The most valuable part of your PC is not
the hardware itself, but I the wealth of personal and often irreplaceable data
stored on its hard drive. From family photos and video, through emails and
household accounts to reports and presentations for work, their loss could
involve time-consuming recovery at best, or be gut-wrenching at worst.
Delete
& Recover Data
Yet it's so easy to make a mistake. All it
takes is one press of the Delete key and your valuable data is consigned to
oblivion. And it gets worse: spinning at 7,200rpm for eight or more hours per
day, it’s a minor miracle that hard disks are so reliable - but nothing is
immune from failure. If your disk suffers a crash it could take with it all
your data. Even something as apparently innocuous as a power failure could
wreak havoc if Windows was writing to your disk at the time.
Before you get too depressed at the
prospect of impending doom, we have good news. Windows may not be able to see a
file that you accidentally deleted or was the victim of a disk failure, but
it's possible that the data could still be there. And if it is still present,
there are several ways in which you can retrieve it.
Of course, there’s a flip side to this.
Sometimes you really do want to delete a file, so it's worrying that apparently
deleted files can be recovered with ease. If you swap PCs with a work colleague
or sell your laptop, for example, you need to be sure that the new user won’t
be able to access the personal data you've previously stored on its hard disk.
Even dumping an ancient computer at the
local tip or recycling centre could be risky. By using some of the techniques
we discuss in the first part of this feature, anyone could gain access to your
passwords, financial details and home address - even if you think such details
have been erased.
Again, with our help, we’ll show you in the
second half of this feature how to ensure that sensitive data is impossible to
recover. You could guarantee this by subjecting the hard disk to some serious
abuse, but we’ll also show you how to securely delete your data in a slightly
less spectacular but more environmentally responsible fashion.
Recovering Data
Chances are you're well aware of Windows'
Recycle Bin; it’s the first place to look if you've accidentally deleted a
file. When you select a file and press the Delete key (or right-click and choose
the Delete option from the context menu), Windows makes no attempt to actually
delete it.
Recovering
Data
Instead, it moves it to a special folder
called the Recycle Bin, which has its own icon on the desktop. Restoring a file
from the Recycle Bin is a matter of double-clicking the desktop icon to display
its contents, then right-clicking a file and selecting Restore.
Don't rely on the Recycle Bin as a safety
net, though: it has a size limit and, once exceeded, older files will in fact
be deleted. The default size is more than adequate for most people, so there's
a very good chance that any files you want to restore will still be present in
the Recycle Bin. To check or alter the capacity, right-click the Recycle Bin
and choose Properties
If you’re in the habit of deleting files by
holding down Shift as you press Del or select Del from the context menu, files
are deleted rather than moved to the Recycle Bin. Similarly, if you choose to
empty the Recycle Bin by right-clicking it and selecting 'Empty Recycle Bin',
the files will be deleted and no longer available to Windows.
When gone isn't for good
The term ’delete’ is something of a
misnomer here, though. Details differ depending on the file system in use (hard
disks often use a different format to flash drives, for example) but, in
essence, all that happens when Windows deletes a file from the hard disk is the
Master File Table (a system file Windows uses to keep track of the physical
area of the disk occupied by each file) is modified. The areas of the disk
occupied by the deleted file are marked as available for re-use.
It should come as no surprise, therefore,
that a software utility capable of delving into the Master File Table should be
able to restore the ’deleted' files. Several programs can do this: turn the
page for a step-by-step guide to using the free DiskDigger utility.
Easily
Recover Deleted Files From Hard Drive, Flash Drives And Memory Cards With
DiskDigger
However, file recovery isn’t always plain
sailing, so it pays to understand its limitations. The most important thing to note
is that time is of the essence. If the areas of the disk previously occupied by
the file are marked as available for re-use, Windows will eventually overwrite
them; when that happens, your data is gone for good.
The sooner you realise you've accidentally
deleted a file, the better your chances of recovering it. Don't save anything
to the disk until after you've tried to recover your data. Given that
installing a file-recovery utility involves writing to the hard disk, it’s
worth installing one now as a precaution. Failing this, look for software that
you can run directly from a USB flash drive, so that downloading and installing
it doesn't inadvertently overwrite the portions of the hard disk that contain
your missing data. Even browsing the web to find an undelete utility causes
files to be written to your disk so, if possible, use a different PC.
Best practice
Undelete utilities are able to work
reliably only with sequential files. If your disk is reasonably full, Windows
will split new files across spare blocks around the disk. Such files are very
difficult to recover.
Different types of drive use different file
systems, and undelete utilities work only with particular types of file system.
Hard disks in Windows PCs use the NTFS file system, but USB flash drives
usually use some variant of FAT (FAT16, FAT32 or exFAT). Be sure to select
software with the necessary support for all your media.
Another drawback with most undelete
utilities is that they won’t work with networked storage, such as NAS drives. The
disks in a NAS drive are under the control of the drive's own operating system
(usually a Linux variant), so software running under Windows isn't typically
able to attempt a recovery. If you’ve accidentally deleted a file then it might
be in the NAS drive's own recycle bin (if enabled), in which case you should be
able to recover it; check the documentation for your model. If it’s not here,
you have only two options.
a
NAS drive attached to wireless route
Provided that you don't mind getting to
grips with the insides of the NAS drive and your PC, it might be possible to
remove the disks from the NAS and attach them directly to your PC. A Windows
recovery utility may then be able to recover your files, but only if the drive
uses the same file system.
Note that NAS drives that use a Raid array
may split your data across more than one disk. Some recovery software supports
Raid arrays, so it’s worth bearing this in mind when making your selection.
If you don't fancy dismantling your NAS
drive, the other option is to send it to a professional data-recovery company.
We'll look at these services overleaf.
