Q I’m trying to install Microsoft Virtual PC 2007 on my computer so that I can run Windows XP alongside Windows Vista but get stuck when it asks where the virtual hard disk is.
Brian Jackson

A Virtual PC does not use ordinary hard disks, instead it creates a file on the Windows hard disk that is used for the Virtual PCs (several virtual PCs can access the same disk, but not at the same time). As you can imagine these files do take up a lot of space.

If you haven’t already installed Virtual PC you can download it from www.computeractive.co.uk/2160279. The wizard for creating virtual computers also creates the virtual hard disk, although it doesn’t really make this very clear and looks more like it is looking for an existing disk.

Click on the New button in the Virtual PC Console window and then on Next. Leave the first option as Create a virtual machine and then click on Next again.

You can just enter a name in the next window and the computer will be created in your My Documents folder. Select the operating system that will be installed on the virtual PC from the list and click on Next twice.

Select the second option ‘A new virtual hard disk’ and click on Next. The file is automatically given the name of the virtual PC so there is no need to change this but check that the size of the hard disk will fit on the computer. Click on Next and then Finish.

The new computer will now appear in the Virtual PC console. Double-click on the icon to start it.