Microsoft has announced the Windows XP end of support date of April 8, 2014. After this date, Windows XP will no longer be a supported operating system.
To help organizations complete their migrations, Microsoft will continue to provide updates to our antimalware signatures and engine for Windows XP users through July 14, 2015.
Note: as previously announced Microsoft will stop providing Microsoft Security Essentials for download on Windows XP on April 8, 2014.
Read the full announcement: