When Windows misbehaves and nothing else works, restoring the operating system via your restore CD or hidden hard-drive partition may be the last resort. So what do you do if you can't find the disc, or if a program that wrote to the boot sector scrubbed the special keyboard sequence for recovering everything and it no longer works?
The first thing to do is get in touch with your system's manufacturer and find out its policies. Some of the biggest PC manufacturers will sell you a recovery CD for around £20 to £30. Recovery media may not be available for older computers, but you should find software on the PC itself for creating a new recovery disc and you might be able to create an installation CD from files on your PC.
If your copy of Windows is currently in good working order, but you don't have a recovery tool, create your own with a good backup program. The resulting recovery disc is arguably better than a factory-issued backup tool, because it will restore a version of Windows that includes all your personalised settings.