Microsoft has filed its first ever loss since it joined the stock market in 1986.
The software giant's revenue rose slightly but due to several one-time items, it posted a net loss during its fourth fiscal quarter, when the Windows division's sales fell 13 percent.
Revenue in the quarter ended June 30 came in at US$18.06 billion, up 4 percent year-on-year but below the $18.13 billion expected by financial analysts polled by Thomson Financial.
The company posted a net loss of $492 million, or a loss of $0.06 per share, compared with net income of $5.87 billion, or $0.69 earnings per share, in 2011's fourth quarter.
The results were significantly affected by two one-time items the company had previously disclosed: a $540 million revenue deferral related to an upcoming upgrade program for its new Windows 8 OS; and a charge of $6.19 billion for the impairment of goodwill on its online services division.
The goodwill impairment is in recognition that its online services division will not grow as quickly as previously expected, an issue related mostly to the 2007 acquisition of aQuantive for $6.3 billion.
Excluding the impact of those two items, revenue would have been $18.59 billion and earnings per share would have been $0.73.
The consensus from the polled analysts was for $0.62 earnings per share in the fourth quarter.
The Windows and Windows Live Division, which includes Windows 7, saw its quarterly revenue drop 13 percent year-on-year, and fall 3 percent in fiscal year 2012 compared with 2011.
The Server & Tools business, which includes products like SQL Server and System Center, posted revenue growth of 13 percent in the quarter and 12 percent in the year.
The Business Division, which includes the Office suite, posted revenue growth of 7 percent in the quarter and the year.
The Entertainment and Devices Division, which includes the Xbox products, increased revenue 20 percent in the quarter and 8 percent in the year, helped primarily by Skype.
In a statement, CFO Peter Klein said the company achieved "solid revenue growth" during the quarter and showed "rigorous cost discipline."
CEO Steve Ballmer pointed out in the statement that Microsoft's business will be driven forward in the coming year as the company delivers the many upgrades it has in the pipeline, including Windows 8 and a new version of Office.