Microsoft Corp kicked off a $300 million marketing campaignon Thursday, aimed at improving the image of its Windows Vista operating system and strike back at Apple Inc’s “Mac vs. PC” ads.

The first commercial of Microsoft’s new marketing push, being created by advertising agency Crispin Porter + Bogusky, aired on Thursday featuring comedian Jerry Seinfeld and company co-founder Bill Gates at a shoe store.

Despite selling more than 180 million licenses since its launch in 2007, Windows Vista continues to suffer from the perception that the operating system is clunky and hard to use compared with Apple computers.

That image has been stoked by Apple’s “Mac vs. PC” ads featuring a geeky and unfashionable PC guy unable to keep up with a better-looking, hip Mac counterpart.

“What the brand stands for, particularly in the case of Windows Vista, has been defined by the competitors. The time is now for us to get in and start telling our story,” said Brad Brooks, a corporate vice president at Microsoft.