The worst PC disasters (and how to survive them)

This costs 3.95p per minute, 1.49p in the evening and 1p at weekends. If you can get online but find some sites are inaccessible, your ISP may be suffering from routing or ISP issues.

Try visiting an anonymous proxy such as The Cloak to see if you can access the sites you need. Or register with the free OpenDNS and use a different group of DNS servers altogether.

My PC keeps locking up and I have to restart it

It's the ultimate in frustration: you've been working for hours on a document, your PC locks up and you've lost everything. Or have you? The first rule is to be patient.

You may get control back without doing anything at all, so wait for at least five minutes to see what happens. Press [Ctrl]+[Alt]+[Del] to try to launch Task Manager, too.

If this loads, press the ‘Processes' tab to see what's using the most memory or CPU time. You might be able to recover the situation by right-clicking that process and setting it to a lower priority.

When these options fail, the keyboard status lights don't change and the mouse cursor is frozen, then there's little hope left. As a last-ditch effort, try a hardware change, such as plugging in a USB flash-drive, or removing and reconnecting your mouse and keyboard (if they're USB models).

If Windows is working at some level then you've a small chance that this might change the situation. If these lockups or reboots happen frequently, your PC may be overheating.

Check the motherboard discs to see if there's a tool you can use to monitor its temperature; if not, look in your BIOS setup program or try third-party tools such as SpeedFan or Core Temp.

If these indicate problems, then remove your PC's case, clean the dust from its fans and vents, and tie up loose cables so they're not blocking air flow. Use your BIOS set-up program for increased fan speeds, and move your PC away from heat sources.

You'll be surprised at the difference this can make.

I'm getting errors on my DVDs

It's good to back up your data to CD or DVD occasionally. But it's bad to leave your files there indefinitely: some cheaper discs can become difficult to read within a year or two, even if they're kept in good conditions.

If you keep anything precious on CD or DVD, make sure you have at least two copies (ideally on discs from different manufacturers) and check them every few months. But you'll still occasionally run into discs with unreadable areas.

This is where specialist assistance is needed. Unstoppable Copier is one of the best free disc recovery tools. It'll repeatedly try to read problem blocks of data, and reconstruct a file even if part of it can't be recovered. CDCheck is good for a second opinion, while ISOBuster comes in both a free and commercial version.

It makes sense to try the free version first, but the commercial edition adds many features, including the ability to recover packet-written data and support for high-def discs. It costs around £16 and the extra capabilities could save you time in the long run.

The full version of this article is published in PC Plus magazine, issue 268.