Why can’t I activate Windows?

Q I used my Aldi PC with Windows Vista offline for around three years after cancelling my broadband internet contract, but decided to get online again earlier this year. Everything was fine for a few days, but then I got an error message that asked for the Windows Vista Premium product code, as the one I had supplied was incorrect.

I entered the code, but it was invalid, and I now have a defunct PC. I contacted Microsoft, which said to keep the PC going I will have to buy a full copy of Vista Premium for £90. Is this right?
Paul Spicer

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A There is no requirement for a Windows PC to be connected to the internet and the initial activation required for a new computer can be handled over the phone. Keeping a PC offline for three years does mean it won’t have any of the Microsoft updates or security patches issued during that period.

These can be downloaded at any time but they should be downloaded immediately, before the PC is used online for anything else.

Three years of trouble-free use means Windows Vista must have been properly activated after purchase, which in turn means that it is a genuine copy of the operating system with a valid product activation key.

To get any further, however, you will need the original Windows Vista Premium box with ‘certificate of authenticity’ and ‘product key’ stickers somewhere on it, or the single-sheet document from Microsoft that came with the PC that provides the same information. Given that you have entered the product key (albeit unsuccessfully), we presume you still have one of these items.

Armed with this information, you need to telephone the UK Microsoft Product Activation Centre. The number can be found by opening the Start menu, right-clicking Computer and selecting Properties. When the window opens, scroll to the bottom and click Activate Windows.

When the Product Activation wizard opens, choose ‘Use the automated phone system to activate’, then select UK from the Country dropdown menu. Dial the displayed telephone number and, when connected, follow the spoken instructions.

If the product activation still fails, you will then be able to talk to a Microsoft support person to sort out the problem, safe in the knowledge that you have a licensed copy of Windows Vista Premium.