Microsoft unveiled Windows Code-Named "Longhorn", Build 4074. This build has a number of improvements over the previous version, Build 4051, which was released in October 2003 at the Microsoft Professional Developers Conference (PDC 2003). People who attended the PDC will be pleased to know that the product keys recieved at that conference will successfully activate this build. The downside to Longhorn is the massive memory consumption issues. WinFS, the new database storage technology, uses upwards to 200MB of RAM, and can easily slow down a system.