Windows XP is set to enter the Extended Support phase of its life, moving out of Mainstream Support, as planned, Microsoft said on Monday. In an email, Microsoft said: “On April 14, Windows XP will transition from the mainstream support phase to the extended support phase, as planned and previously announced.”Mainstream Support usually only lasts five years, but in this case it lasted 7 1/2 years, because of the delay in delivering Windows Vista, as well as (let’s be honest) the basic dissatisfaction with Windows