Struggling music subscription service Napster is blaming Microsoft for its problems.

Napster chairman and chief executive Chris Gorog said: "There is no question that their execution has been less than brilliant over the last 12 months. Our business does rely on Microsoft's digital rights management software and our business model relies on Microsoft's ecosystem of device manufacturers."

He said Microsoft had a complex task dealing with various devices and services, in comparison with Apple's focus on one device and one service. Gorog was speaking at a Reuters event in New York.

But he remains confident that Napster has made the right strategic decision and that non-iPod players will start to gain market share - he believes the market will look very different in one or two years.

He said: "Ultimately, the consumer electronics giants...are all going to come to this Windows Media party. This is really going to be the ubiquitous format."

Gorog again dismissed rumours that Napster is up for sale. ®