Creating C# DLLs accessed through VC++ (and vice-versa), is it possible?

You can access dlls from C#, but you need to import the api of the dll by using the dllimport attribute followed by the exact prototype of the API call equivalent in C#(return type - function name - parameters). You can call C# assemblies from VC++ if you put a COM wrapper around the assembly (the assembly must be a class library though). You can use attributes such as progid and dispid to further detail the COM interface in your C# assembly. You will also need to set a property in your Project (in Visual Studio) called register for COM Interop so that the assembly is automatically unregistered and registered with COM each time you build a new assembly or change the interface in VS.NET. -Mike G.