Virtualisation offers a potential solution to many PC disasters, particularly those stemming from malware. If you're running a correctly configured virtual machine, you can click around in the internet's darker corners safe in the knowledge that little damage will be done to your PC. You can also install apps with dubious provenance in relative safety.

Why? Because when you're done, you can kill the virtual PC you've just abused and start a new one afresh. Any malware you've contracted will be flushed away into the digital void. It's a compelling idea, but it's not without its pitfalls.

Firstly, you'll need a beefy PC with lots of memory – Windows needs 2GB of memory to run as a minimum and you'll need to give your VM the same. So, for a slick VM, your host PC needs at least 4GB of memory.

Virtual pc 2007

Virtual machines exist as a space on the host's hard disk, so it will need a lot of space. A VM can consume tens of gigabytes of space, so be prepared for your disk to fill up quickly if you don't delete unused machines.

Finally, some virtualisation systems demand processors that support virtualisation at the hardware level. If you're an AMD fan you'll need AMD-V, while Intel users should look for Intel VT support. Windows 7's virtual XP system (XP Mode) demands CPU-level virtualisation support.

Next, remember to remove any drives shared between your virtual machine and the host PC before accessing the internet. This will cut off a line of contagion between the VM and the host. Indeed, it's generally considered safest to have the host and the VM running different OSes.

If you host a Windows VM on a Linux platform, some (but not all) types of Windows contagions will be better contained. Run a Windows VM on a Windows PC and malware could execute in the virtual environment, penetrate the host and continue spreading around your network.

Antivirus protection

You must also have solid malware protection on the virtual machine and the host. Malware will still function on a VM – and if you're entering your bank log-on details, a keylogger can still report them back to its makers from within a virtual environment.

We recommend going for a free antivirus program such as AVG or Microsoft Security Essentials for your virtual machine. Run a full paid-for suite and you may encounter difficulties with activation when you've restarted your VM a few times.

Don't just consider a virtual machine a super-safe surfing system, though. A VM with all your favourite apps is also a super-safe working environment. You may not enjoy using Linux for your leisure time but prefer its inherent stability and security for work. Build a Linux VM and you'll get the best of both worlds.

Most virtualisation systems let you create a new virtual machine at the touch of a button. As you develop your VM's look, feel and function, you can save its state, which means that over time you'll be able to create your ideal extra-secure – and hopefully disaster-proof – virtual machine.

Take action: Create a Virtual PC

If you're using Windows 7, setting up a safehouse virtual machine with which you can explore the deepest reaches of the internet is easy. Start by grabbing Microsoft's freely available Virtual PC 2007. Download the version appropriate to your OS (you'll find both 32-bit and 64-bit versions available).

Next, run the set-up executable, click through the installer (you should find the product key added for you; VPC was once a commercial app, but Microsoft has now released it for free) and then run the installed app.

The first thing that will happen is that a wizard will pop up. Here you can configure the settings of your new VM. To get started, choose 'Create a Virtual Machine', give it a name, choose your desired OS (use 'Other' if you're going to install Linux) and allow it to use the recommended level of RAM (as long as you have it available, of course!).

Choose to use a new virtual disk when asked – this is a sandbox file in which your new OS will live. Now put the install disc of your chosen operating system into your optical drive, doubleclick your virtual machine in the list and choose the appropriate drive in the CD menu to begin installing the VM's operating system.

Survival items every PC owner needs

Below you'll find the items that every careful PC owner should have in their disaster survival kit, from preventative tools to ward off common problems to the items you'll need if the worst happens and something does go wrong. Keep these things handy and you'll be ready for (almost) anything.

1. Compressed air

Dust can slow down fans – and if air isn't drawn away well enough, the component can overheat and eventually fail. A blast of compressed air will shift most build ups.

2. Thermal paste

This provides a thermally conductive substrate between components and their coolers. It can degrade, so remove the older paste from time to time and apply a new layer.

3. Screws and washers

Vibrations inside your PC can lead to fan failure. Secure components properly with washers and ensure you attach the right number of screws to motherboards and drives.

4. Cable ties

Secure your cables with cable ties to improve airflow through your case and aff ord easier access to your motherboard and other core components.

5. Windows boot disc

The recovery interface for Windows may be a brick wall of DOS commands, but it can still sort out problems with the Master Boot Record and your Windows installation.

6. Thumb drive

If your machine refuses to boot but you can access the drive via a boot disc, recovering your fi les may be your main concern. A small USB drive can help you to get those files off the machine prior to a reinstall.

7. A Philips screwdriver

This is realistically the only tool you ever need for removing components that you suspect may have failed.

8. Netbook

The internet is a mine of knowledge for sorting out PC problems. A second machine enables you to continue searching for solutions should your main PC go down.

9. CMOS battery

If your CMOS settings aren't being retained, your CMOS battery will need replacing. These large disc batteries are increasingly becoming available from supermarkets.

10. A boot disc

If you're having no luck with the Windows boot disc, turn to a third party for help. We recommend one from the impressive collection over at www.bootdisk.com.

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First published in PC Plus Issue 292

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