LOS ANGELES — Less than a year after Microsoft entered the tablet computer market with the Surface, the cracks are starting to show.
The software giant on Thursday booked a large write-off to its Surface RT business after it slashed prices on the tablets to stimulate demand this week. Its quarterly earnings results also showed that Windows 8, an operating system designed to bridge the divide between PCs and tablets, has been so poorly received that it contributed to a revenue drop in its operating system software unit.
The missteps in both strategic product lines disappointed Wall Street and shares plunged nearly 7 percent to $33.10 in after-hours trading Thursday.
The write-down for expected losses on the Surface RT tablet amounted to $900 million. Even without it, Microsoft's results would have fallen short of expectations.
The results came a week after the company announced a major reorganization to help it transform into a "devices and services" company that is less reliant on providing software for personal computers. The earnings miss raised new questions as to whether the transition will succeed.
"It doesn't inspire a lot of confidence," said Nomura Securities analyst Rick Sherlund. "You're in the hardware business now, and pretty shortly after entering it you have a pretty big write down. That's embarrassing."
Both Windows 8 and the Surface tablet represent Microsoft's big bets on the tablet computer market as PC sales continue to decline. Research firms IDC and Gartner said last week that global PC shipments fell 11 percent in the April-June quarter. It was the fifth consecutive quarterly decrease.
Acknowledging the company's difficulties with the change, Microsoft Chief Financial Officer Amy Hood told investors on a conference call that "this journey will take time."