It's an event that Microsoft has been warning people and businesses about for months. And it is one that hi-tech thieves have been looking forward to as those digital protections start to diminish.
In a bid to get users shifting over to a more modern version of windows, Microsoft has created a website that tells people if they are, or are not, running the software and on 8 March will make a pop-up warning appear on the screens of those who are still using it.
Microsoft is also working with some other software firms to help people work out how to update and upgrade and has made tools that transfer data and settings over to a new version of Windows so the switch is as painless as possible.
Long life
Windows XP (for "eXPerience") went on sale in October 2001 and has proved remarkably resilient.
Figures from market research firm Net Applications suggest that it was the most widely used Microsoft operating system until August 2012 when it was overtaken by Windows 7.
The software is still popular in many government departments and some studies suggest the majority of the world's cash machines still run it.
Delays in the versions of Windows that came after XP extended the support life for the operating system. Add to this the hard work it takes for companies to get applications running on new versions of Windows and its no surprise that companies have stuck with it.
