Recover files from a failed PC's hard disk

Q In your article 'Recover deleted data from your hard disk' you say I will be able to rescue files from a hard disk by removing it from the computer’s case and placing it in a disk caddy to connect it to another computer.

Some time ago I was told my old Windows ME computer’s hard disk had failed. It was replaced and the useless hard disk was given back to me.

I would like to try and retrieve photographs from it but I don’t know what a disk caddy looks like or how to use one – I would probably end up buying a tea caddy rather than a disk caddy.

Could you explain how to buy and use a disk caddy, please?

B Williams

A The first thing for us to say is that if your hard disk has failed entirely it is unlikely you will be able to rescue the files on it using the method described.

There are several ways in which a computer can fail, and in the article to which you refer we were discussing a computer that has failed in another way.

For instance, if your motherboard fails, you can rescue the files from the hard disk in the way described. But if the hard disk itself fails the files on it cannot usually be recovered.

However, there are levels of ‘failure’ and, depending on what you were told by the person who fixed the computer before, it may not have failed completely. In that case it may be worth trying the disk caddy method to see if some files can be saved.

A disk caddy is really just a box into which you place a computer’s internal hard disk. It has connections inside the box for the hard disk, and once those are attached you can plug the caddy into a computer’s USB port, at which point it will act just like any other external hard disk.

There is one complication though. There are several kinds of hard disk, and you will have to buy a caddy that is compatible with yours.

If you are using a laptop computer it’s likely the hard disk will be a 2.5in model whereas for desktop computers it will usually be a 3.5in model (the size refers to the hard disk’s width, but the connectors are different on each, too).

Both sizes of disk come in two kinds as well, IDE and serial ATA (Sata). IDE is older, so if your computer is older than four years of age, it will almost certainly use an IDE disk, while computers younger than three years will almost certainly use a Sata disk.

If it’s between three and four years old, it could be either.

So there are four kinds of disk: 2.5in Sata, 2.5in IDE, 3.5in Sata and 3.5in IDE and you must get a product that copes with your computer’s hard disk.

One product we looked at recently, the Sandberg Sata Docking Station, can cope with both 2.5in and 3.5in Sata disks but not IDE ones, for instance.

Alternatively, the Maplin USB2 to Sata/IDE Combo Adapter can work with all four kinds of disk, but it’s not strictly a caddy: it’s just a cable that plugs into the computer’s USB port, and into the other end you plug the hard disk.

You need to be a bit more careful doing it this way as it means leaving the hard disk exposed on a table where a knock or a spilt coffee cup could have unfortunate consequences, but it is more flexible, particularly if you can’t tell in advance what kind of hard disk is in your computer.

You can watch a video on installing a 2.5in hard disk in a caddy on the Computeractive video section and a 3.5in hard disk.

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