Microsoft ends support for Windows XP on April 8, 2014.
For more information, visit https://www.microsoft.com/en-us/windowsforbusiness/end-of-xp-support.
After the next official quarterly update (expected May 2014), Adobe will no longer develop versions of Acrobat or Reader for Windows XP. Also, Adobe will no longer test releases or patches on Windows XP or fix bugs specific to Windows XP.
Windows XP will be removed from the system requirements (tech specs). Adobe won't fix any Acrobat or Reader bugs specific to the Windows XP operating system. You can run Acrobat or Reader on a supported version of Windows, such as Windows 7 or 8.
You can continue to install and use Adobe Reader and Acrobat on Windows XP. However, you won’t benefit from future security updates or patches. If you are entitled to support, Adobe will continue to support you, unless the problem is isolated to Windows XP. We recommend that you run Acrobat and Reader in an operating system that both Microsoft and Adobe support (Windows 7 or 8).