Repair Installation: Get a New PC in 30 Minutes

#1 Remove Service Packs
If you've installed a Service Pack since Windows was first installed or loaded on to your computer, you'll need to remove it first. Open the Programs and Features Control Panel and select 'View installed updates' Scroll down, select'Service Pack for Windows'and click'Uninstall to remove it.

#2 Start repair process
The repair installation process must be run from Windows itself- boot into Safe mode if necessary to start it Pop your Windows disc into the drive and if the Autoplay dialog box appears, click 'Run setup.exe'. If it doesn't appear, click 'Start > Computer/and double-click the DVD drive icon.

#3 Get updates
Click 'Yes, followed by'Install now' to start the repair installation process. When you're prompted, click/Go online'to get the latest updates for installation (recommended) and then wait for them to be downloaded. Once this is complete, the process will restart automatically.

#4 Choose upgrade installation
Read the licence terms and conditions, then tick 'I accept the license terms' before clicking 'Next: Windows Vista will now ask you to enter your product key (Windows 7 will skip this step), then at the next screen choose 'Upgrade'. Now wait while the compatibility check is performed.

#5 Make a cup of tea
Once complete, Windows will install over the top of itself, following a similar - but not identical - process to a fresh install. It will restart several times during the process, but can be safely left to its own devices. Expect this to take half an hour or so.

#6 Complete repair process
When prompted, enter your product key and click 'Next'. Choose Use recommended settings', then work your way through the rest of the setup wizard verifying your time zone and network settings - click'Skip'to ignore any irrelevant parts.