microsoft will pull the plug on technical support for its windows xp operating system. xp was introduced in 2001. since then, microsoft has launched four new operating systems, but a lot of people still rely on xp. here's anthony mason. >> reporter: at the donut plant in new york city, the cash registers still run on windows xp. >> i haven't had a need to change because it didn't break. >> reporter: chief operating officer k.c. salazar isn't alone. up to 25% of consumers and businesses, including cbs news, are estimated to still be using the 12-year-old operating system. but microsoft, on its web site, is counting customers down to zero hour at midnight tonight. >> does that mean the machine is going to blow up? not necessarily. >> reporter: but ismael matos