Now boot your infected PC from the new rescue disc. If you persevere there's a good chance the infection can be fixed.
I've accidentally deleted my files
It might have taken weeks, months, even years to create your document, but you can still delete it in a second. And if you empty the Recycle Bin before noticing, or it doesn't get there, then you'll need third-party help to restore the situation.
If you don't currently have any undelete software on your PC, use another system to download a copy of Tokiwa DataRecovery and copy it to a CD or flash drive.
It can then be run from there on your own PC, no installation required, which reduces the chance that you'll accidentally overwrite the data you're trying to save. You'll get better results from more powerful programs, such as SoftPerfect File Recovery or Undelete Plus.
The latter is most impressive, working on just about every version of Windows from 95 to Vista, so it's best to install one of these now in order to ensure you're prepared when any problems crop up.
Somebody stole my PC
Having your system stolen means not only have you lost access to your data forever, but someone else could be browsing it, recovering usernames, passwords, credit card numbers and more.
All you can do to guard against this is encrypt the contents of your hard drive. If you have the Enterprise or Ultimate version of Vista then you'll be able to take advantage of Microsoft's new Bitlocker encryption system.
But if you haven't, there's no need to feel left out. CompuSec is a free alternative that, if anything, is more powerful, as it encrypts hard drives, CDs, DVDs, memory sticks and more, and works with Windows 2000, XP and Vista.
The CompuSec set-up process can take a long time – unsurprising as it has to encrypt your entire drive. (That's a scary prospect in itself, so we'd recommend you run a backup first, just in case there are problems.)
But once installed, it's all very straightforward: enter your password before Windows starts and all encryption and decryption is automatically carried out in the background.
There's a small performance hit for this, but if you've got any confidential information on your hard drive, the extra security makes it worth the effort. If you'd like a chance to get your stolen kit back, then you can also sign up for one of many alert services.
These typically install something on your PC that will tell the service whenever it goes online, helping to track down the thieves.
My Internet connection doesn't work
You never quite realise how much you depend on Internet access until, suddenly, it isn't there. You can't use your email, download things or do that research. Rebooting your router could be a quick solution.
Or there may be a local networking problem: right-click the network icon in your system tray and select ‘Repair' to give your system the chance to fix things. Check your modem, too.
There's probably an indicator light that tells you whether it's receiving a signal from your local exchange (assuming you're using ADSL). If the signal is down and restarting the modem doesn't help, it looks like there's a significant outage and you should let your ISP know.
If your broadband is down, you could try the alternative of a dial-up connection – assuming you've got a dial-up modem and a suitable cable. Free UK ISP is a good example: you can get online with them using the number 0844 711 0059, the username ‘freeisp@internet' and the password ‘Internet'.