UPDATE 1-Microsoft profit below estimates after tablet charge
* Q4 EPS $0.59 versus Street view $0.75
* $900 mln charge for inventory of Surface RT tablets
* Slow PC sales hit Windows business
SEATTLE, July 18 (Reuters) - Microsoft Corp on Thursday reported lower-than-expected quarterly earnings as slow personal computer sales ate into its Windows business and it took an unexpected $900 million charge for its inventory of unsold Surface tablets.
The world's largest software company reported fiscal fourth-quarter profit of 59 cents per share, compared with a 6 cents per share loss in the year-ago quarter when it wrote off the cost of a failed acquisition.
Wall Street had expected earnings of 75 cents per share, on average, according to Thomson Reuters I/B/E/S.
Revenue rose 10 percent to $19.9 billion, helped by sales of Microsoft's Office suite of applications, but fell short of analysts' average estimate of $20.7 billion.
Microsoft said the $900 million charge related to its Surface RT tablet, which was launched alongside Windows 8 in October but has not sold well.
Earlier this week, Microsoft said it was drastically cutting prices and expanding distribution of the model to entice buyers.