QUESTION I upgraded my HP netbook from Windows 7 Starter Edition to Home Premium. Following a fault, I returned the netbook to HP for repair. It came back fixed, but with the original Starter Edition installed. Can I reinstall my copy of Home Premium using the original activation key? Kevin Pauling

HELPROOM ANSWER You should be able to use the same key; if it fails, you can get a new key from Microsoft for free. Ensure you're connected to the internet, then go to Control Panel, System and, under Windows Edition, click 'Get more features with a new edition of Windows 7'. This will open Windows Anytime Upgrade and invite you to enter your key.

If it's rejected, advice will be given on gaining authorisation, which takes only a few minutes over the phone.

See also: How to fix everything: the ultimate guide to fixing technology

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