I don’t know whether you’ve heard of WannaCrypt ransomware that’s been in the news lately.
Microsoft made a patch in March that’s supposed to fix that problem, but I checked some computers and found that the update wasn’t installed on them and wasn’t available in the ‘new updates’ area in Windows Update – even after I had installed all the available Windows updates!
So I had to manually download and install the patch.
You can find the patch here:
https://technet.microsoft.com/en-us/library/security/ms17-010.aspx
In the ‘Operating System’ column (the left-most column in the table), you can click the link for whichever operating system’s patch you want. Clicking a link should take you to a Microsoft Update Catalogue page from which you can download the update.
You may notice that some of the updates are ‘Monthly Rollup’ updates and some are ‘Security Only’ updates.
If you click either of the links for the Windows Vista updates, it’ll take you to the same Windows Update Catalogue page. You can find the Windows XP updates on that page.