The architecture, interface, and functionality of the Windows Application Programming Interface (API) make it difficult to master and use effectively, and contribute negatively to the safety, robustness, and portability of the applications developed under it. The API is structured around a large and constantly evolving set of functions and is based on a problematic shared library implementation. The provided interfaces are complicated, nonorthogonal, abuse the type system, cause name-space pollution, and use inconsistent naming conventions. In addition, the functionality of the interface suffers from inconsistency, incompleteness, and inadequate documentation. Application developers, programming tool vendors, and Microsoft should face the above problems and provide appropriate solutions.