SAN FRANCISCO: Microsoft is counting down the days until it is through with the Windows XP operating system for personal computers.

The US software titan used a blog post to remind the world that in two years it will no longer support the generations-old operating system that people have clung to despite the releases of successors Vista and Windows 7.

“We want to acknowledge the two-year countdown to the end of Windows XP and Office 2003 support,” said Microsoft marketing director Stella Chernyak.

“Windows XP and Office 2003 were great software releases for their time, but the technology environment has shifted.”

She advised computer users, particularly businesses, to begin “migrating” machines to the latest versions of the programs well before Microsoft puts XP to rest on April 8, 2014.