There are still a lot of XP users out there, and this latest episode of malware (“Ransomware”) is mainly affecting XP systems as there have been few (none) updates to XP for quite a while.
However, Microsoft have now provided a special fix for this issue – KB4012598.
All XP users should apply this now unless it has already been picked up by the Automatic Updates process and I suspect that many users will have turned Automatic Updates off?
Note 1 : If you need to do this manually you should go to Microsoft KB4012598 download to download the fix.
Note 2 : If you find that that fix does not apply (“does not match your system”) then be aware that there are two types of Windows XP called “embedded” and “non-embedded” … it doesn’t matter if you do not understand the difference as the following website will explain and provide links to other versions of KB4012598 … KB4012598 Alternative Formats
… Select one of the links at the end of the article to download an alternative version … (probably either “Windows XP SP3 x86” or “Windows XP Embedded SP3 x86” for most home users). If that fails, try the other.