Just how popular is Microsoft’s software lately?

The latest iteration of Microsoft’s Windows operating system, Windows 7, has sold 240 million copies in its first year of being on the market, Microsoft announced today.

Add that to the roughly 6 million downloads of the newest version of its web browser, Internet Explorer 9, and its newest mobile operating system, Windows Phone 7, which shows some promise in being able to compete with the rest of the heavy hitters on the market, and you have a potential comeback story.

Microsoft has been a bit of a black sheep, criticized for failing to innovate with its flagship operating system and mobile platforms as companies like Google and Apple waltzed in and took over the market. Its Windows Vista operating system, released almost four years ago, was panned for being slow and bloated, and Internet Explorer 8 faced much of the same criticism that Internet Explorer has always faced. Microsoft responded by stripping down its PC and mobile operating systems, as well as its web browser, to provide a more user-friendly experience.

The results seem to be positive. Internet Explorer 9 was downloaded about 2 million times within the first two days of launching. All of Microsoft’s manufacturing partners were shipping machines with Windows 7 as well, compared to only about 70 percent that were shipping PCs with Windows Vista. Windows 7 is also now running on 17 percent of all PCs in the world, as well as 93 percent of new PCs, according to Microsoft.

The company still has a little ways to go in the mobile market — on its current trajectory, Windows will continue to lose market share to Apple, Research in Motion and Google, according to a report by Gartner. But if Windows Phone 7 ends up being anywhere close to as successful as the iPhone or any of the Android handsets, Microsoft might just be back in the game.