Windows XP Service Pack 1

On October 10, 2006, Microsoft will end all public assisted support for Windows XP Service Pack1 (SP1). After this date, Microsoft will no longer provide any incident support options or security updates for this retired service pack under the policies defined by the Microsoft Support Lifecycle policy.

To enhance the security of your computer and to continue to receive updates for Windows XP, we recommend you upgrade your computer, for free, to Windows XP Service Pack 2 (SP2).

Suppose I best get patching these users.....

Microsoft Source