Microsoft's website bluntly said that the OS is a dead man walking and if users have not started the migration to a modern PC, they are late.
Microsoft quoted data that claimed OS migration programs in businesses take between 18 and 32 months to complete.
The company announced what it called a "two-year countdown" to the death of Windows XP. Windows XP and the business productivity suite Office 2003 both exit all support on April 8, 2014.
Writing in the Microsoft bog, Redmond warned that on that date it would stop shipping security updates for XP and Office 2003.
XP went on sale in October 2001 while Office 2003 launched October 2003.
To be fair, 12 years is a long time to support anything, and XP has been on the shelf for two and a half years longer than Microsoft's usual practice - and a year longer than the previous record holder, Windows NT, which was supported for 11 years and five months.