One year ago, Microsoft released a major update to its Windows OS: Windows 10.

Windows 7 and Window 8.1 users were able to grab the upgrade at no cost, but all that's about to change. Microsoft said it would only let users update - free of charge - for a year. In other words, when 29 July 2016 rolls around, the company will stop being so nice. You therefore only have one day (or mere hours) to get Windows 10 for free. Microsoft's free offer will expire at 11:59 pm UTC-10.

After that, if you want the upgrade, it will cost you $119/£100. Now is the time to get out your old laptop, desktop, or tablet computer, and ensure it's up to date. Honestly, we'd be surprised if you haven't done that already, because Microsoft has been a little aggressive about update requests. Users of Windows 7 and 8.1 should be familiar with those daily popups urging them to "Get Windows 10".

In some cases, Microsoft even automatically scheduled a date and time for PCs to update to Windows 10. If you've managed to avoid all that, but now find yourself in a hurry to get your copy, Pocket-lint has a step-by-step guide that'll help you. Keep in mind once you update, your PC will be licensed for the new OS, so you could roll back to Windows 7/8.1 but then update again for free.

Also, in order to take advantage of the new Windows 10 Anniversary Update, which release 2 August, you'll of course need to be running Windows 10. The clock is ticking, so act fast.