Hey I have the same problem, I am evaluating if i really have to use C++ for doing the job. You can of course create a COM Server in any COM compatible environment, so also in .NET. I am by far not in any usable state, but I can tell you what I did so far. First, the msctf.dll only has a header and an IDL file (in Windows SDK 7.0), which has to be modified such that you get a type library (tlb). I