Software giant Microsoft has finally walked away from XP SP2 and said it will not give a monkey's if hackers work out a way of cracking it.
Windows 2000 has also been dumped, but that is so old now and was never as popular.
The software giant said that it will stop supporting computers using those older operating systems as of today.
It is probably the first time that Microsoft has had to cull an operating system while it is still under the bonnet of a huge chunk of PCs.
The SP2 version of Windows XP was horrendously successful and analysts tell us that half of Windows XP machines used by businesses are SP2 machines.
With no new security patches for Windows XP SP2, users will not get updates to the core operating system and its components and will become increasingly susceptible to attacks.
Most XP machines, particularly those in homes, are running SP3.
Microsoft hopes that instead of updating to SP3, businesses will buy new Windows 7 PCs.