Microsoft's advertising business struggled to compete with rival Google
Computing giant Microsoft has made the first quarterly loss in its history after it wrote off some of the value of its online advertising business.
The loss came after it wrote down the value of Aquantive by $6.2bn (£3.94bn; 5bn euros), which failed to bring the profits expected by Microsoft.
That led to a $492m loss in the three months to the end of June, compared with a profit of $5.9bn a year ago.
The company has not made a loss since it joined the stock market in 1986.
It took over Aquantive in 2007 but it struggled to compete with rival Google.
Microsoft paid $6.3bn for Aquantive.
Microsoft is doing well in other areas, despite the decline in popularity of its Windows operating system, which dominated the personal computer market for years.
Revenue for the three months to June rose by 4% to $18.06bn.