Why is my computer making a scratching noise?

There are two possible explanations for this. Either a mouse has found a way inside your computer – and we’re not talking about the thing that moves the cursor – or your hard disk is in grave danger of failure.

A hard disk is a bit like a vinyl record player, except the heads hover over the platter when reading data instead of a needle physically dropping onto the disk as they do with an LP. When a hard disk starts making a scratching or grinding noise, it’s normally a sign that the heads are coming into contact with those highly sensitive glass platters and that’s very bad news indeed. Terminal, in fact.

If you’re a wise owl, your computer will be backed up on a daily basis, meaning any data loss should be minimal. If you’ve taken a more laissez-faire attitude to backups, then you’re in something of a bind.

The longer you leave that computer running, the more chance you have of causing permanent damage to those hard disk platters and all that data being lost forever. However, unless you’ve got a clean lab, a degree in mechanical engineering and several grands worth of specialist equipment in your back bedroom, you’re unlikely to be able to recover the data yourself anyway.

Instead, if you want those photos of last summer’s holiday to Tenerife back, you’re going to need to send the hard disk to data recovery specialists such as Ontrack. We’ll warn you now, you’re likely looking at a bill that runs well into the hundreds of pounds to recover the data and have it sent back to you on a new hard disk.

The moral of the story is, of course, to always keep backups (Mark has some advice on changing backup disks here). Hopefully, you read this sentence before something goes wrong…

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