The message "unresolved external symbol WinMain referenced in function WinMainCRTStartup" is one of those incomprehensible error messages in various versions of the Embedded Visual C++ development system and its variants. In my experience, it usually happens (indeed, it so happened today) when you import a project or project components originally created using another version of Embedded Visual C++ or perhaps the regular version of Visual Studio. While it can cause hours of frustration, the fix seems surprisingly simple.

All that needs to be done is to change the name of the Entry-point symbol. It may be set to WinMainCRTStartup. What is actually needed is wWinMainCRTStartup: