BELLEVUE, Wash. — It used to be that a new version of the Windows operating system was enough to get people excited about buying a new computer, giving sales a nice pop.

Not this time. Windows 8, the latest edition of Microsoft’s software, failed to pack shoppers into a Microsoft store in a mall here last week, when parking lots in the area were overflowing. The trickle of shopping bags leaving the store with merchandise was nothing like the steady stream at a bustling Apple store upstairs.