Microsoft Corp. launched its Office XP business-applications package, the first Office update in two years, and called it the most significant new product it will launch this year. Microsoft later in the year will launch Windows XP, an update to its other key desktop software product, the Windows operating system. Desktop applications, which once posted double-digit sales gains, were up 7% in the first quarter. Microsoft stock bottomed in December at nearly $40 but has recovered and is up around 60% for 2001 to date. In trading Friday, Microsoft closed down 0.6% for the week.