Microsoft will support its Surface Pro tablet until July 2017, or almost four-and-a-half years after its launch last weekend, the company’s website confirmed. Like its predecessor the Surface RT, the Windows 8-powered Surface Pro sports a support lifecycle that’s less than half the usual 10 years Microsoft allots its software products. Microsoft will support the Surface Pro only in a “Mainstream” support phase, the company said on its lifecycle website. Last year, Microsoft announced a similar support schedule for the Surface RT. That device, which launched in late Oct. 2012, will be supported until April 2017, or nearly four-and-a-half years. Microsoft typically supports consumer-grade software only during a five-year mainstream stretch. Business software and operating systems receive another five-year span, called “Extended” support, for a total of 10 years.