Can I install the 64-bit edition of Windows from a recovery disc?

Q I have a PC running the 32-bit edition of Windows 7. The PC currently has 4GB of memory, which I'd like to upgrade. I understand that the 64-bit version is required for this to be possible.

My computer came with a pair of recovery discs, apparently containing both the 32- and 64-bit editions of Windows 7.

Is it possible to use the 64-bit disc to upgrade my PC or will that delete my files, folders and applications? If the latter, can I save my existing setup so it can be re-installed after I have put the 64-bit edition of Windows 7 on my PC?

I'm also concerned because I have only one ‘product key' – will this work with the 64-bit recovery disc?

Brian Marshall

A That's several questions for the price of one. We'll try to answer them in the most logical order.

First, it is important to understand the difference between recovery discs and original installation discs. Recovery discs are designed to return the PC to its original state, as if fresh from the factory.

So using one will wipe everything off the computer – including all your personal documents.

Next, once activated, the one product key you have will have been tied to the version of Windows used on the PC – the 32-bit edition of Windows 7.

At some point the choice was made (by you, at the point of purchase or first setup) to use the 32-bit version, so that's the version to which your product key now relates.

The manufacturer supplied both 32- and 64-bit recovery discs as standard with all PCs leaving the factory. These discs are useless without a valid product key.

To recap, all you can do with the recovery discs is to restore the PC to its factory state, with the 32-bit edition of Windows 7 – and this won't help you achieve the memory upgrade.

So, if you're determined to break the 4GB memory barrier imposed by 32-bit operating systems, you'll need to purchase and install the 64-bit edition of Windows. But the bad news here is that it is not possible to use the ‘Upgrade' option when replacing 32-bit Windows 7 with the 64-bit version.

In other words, you'll have to choose the ‘Custom' install option, which will result in a clean installation of Windows 7. There is no practical option but to re-install your favourite applications.