Recovering lost data

Posted on 19 Jan 2007 at 15:37

• 
• 
• 
• 

 1 of 4

Gallery

Deleting an important file needn't be a disaster. With the right software and bit of know-how, deleted files can usually be recovered.

Accidentally deleting an important file is something that has happened to almost all of us at some point. The file in question is invariably something irreplaceable, so it is no wonder that panic is the usual reaction. But with the right piece of software it's usually possible to recover deleted files. This is because they aren't really gone, they've just been removed from Windows' 'table of contents'. In this feature, we'll show you how to get them back.

How Windows stores data

Before we look at how to go about recovering lost data, it is useful to know how data is stored on a hard drive in the first place. A drive is divided up into a number of sectors, each of which can house a file or a portion of a file. Files that are larger than the size of a single sector can be split across several sectors. When a file is saved, Windows uses any available sectors in the order they appear on the hard drive.

When a file is 'deleted' it is not actually removed from the hard drive. Instead, the relevant sectors are marked as being free, so they can be used the next time a file is saved or created. Data recovery tools take advantage of this to restore files that have been deleted. With this in mind, once you have discovered that a file has been accidentally deleted, it is important that you stop using your PC before the file's disk sectors are overwritten with other files. At this stage, the best option is to switch off your computer, remove the hard drive and install it in a second PC from where you can use the data recovery tools outlined below.

In order to reduce the risk of overwriting deleted data, it is a good idea to take the precautionary measure of storing documents on a separate partition from Windows itself. That way, if you do delete a file, there's little chance of it being overwritten. Using a partitioning tool such as Partition Magic (www.symantec.com), you can divide up your hard drive into two or more partitions - one for Windows and one for the My Documents folder, or whichever folder you want to use to store files.

Methods of recovery

There are a number of programs on the market that can be used to recover supposedly deleted files, ranging hugely in price. In the vast majority of cases, you should find that provided you have followed the previous advice of not using the hard drive after discovering files have been accidentally deleted, one or more of these programs will be able to get your data back. Should you find that recovery is not possible, there are still avenues you can investigate. In extreme cases, you may have to send your hard drive off to a team of data recovery experts and again there are a number of services to choose from.

But first we'll take a look at some of the software options available to you, starting with a free program in the form of PC Inspector File Recovery 4 (www.pcinspector.de). Despite being free of charge, it offers a number of recovery options, including recovering files that have simply been deleted, retrieving files following a drive format and restoring a partition or drive that has been lost. After a scan of the problematic drive, the program will display a list of all files that have been detected, including details of their original locations and their current state - an indication of the likelihood of successful recovery. This program is superb and there's no arguing with its price tag.