In the US and Europe the firm will focus on making the upgrade versions cheaper while in emerging markets they will focus on making the full versions a lot cheaper.
"We anticipate these changed will provide greater opportunities ... to sell more stand-alone copies of Windows," said Brad Brooks, a Microsoft corporate vice president.
In the United States, Microsoft will reduce prices for Windows Vista Ultimate, the company's top-end operating system, to $319 from $399 for the full version and cut the price for an "upgrade" version to $219 from $259 for consumers who already run Windows XP or another edition of Vista.
It also cut prices for upgrade versions of Vista Home Premium, its mainstream product, to $129 from $159. The price cuts vary by country.
In emerging markets, Microsoft will stop selling "upgrade" versions of Vista, because, for many customers, it will be the first purchase of a genuine copy of Windows. The company will instead sell Vista Home Premium and Home Basic, a stripped-down version, at the upgrade prices.