Windows 3.1 build 038

Windows 3.1 build 038 is an unleaked build of Windows 3.1, mentioned in an internal Microsoft e-mail from early 1991-07. The e-mail discusses issues with Microsoft Flight Simulator 4.0 running on this build.

Flight Simulator is reported to be slow and experiencing color mapping issues on this build, and there is a rare bug which causes massive screen draw problems. It is also said scrolling is smoother when Flight Simulator is running in a DOS box on OS/2.