I will thank you hieronymus1 if you find that code. I need it for something important.

About what Wilfried said:

The type library is called mpna82.tlb and it's in the folder where you install MapPoint. I import it in my code. And the compiler generates two files mpna82.tlh and mpna82.tli that contain definitions of all structs, enums, and so on, and functions to call MapPoint functions, for example:

LocationPtr Location::GetLocation ( ) {
struct Location * _result;
HRESULT _hr = get_Location(&_result);
if (FAILED(_hr)) _com_issue_errorex(_hr, this, __uuidof(this));
return LocationPtr(_result, false);
}

is defined in mpna82.tli.

I don't know how to solve this unresolved external symbol the linker gives me.

I have another question about the COM programing. Is it possible to compile the C++ app under linux, tu execute it under linux, if you have your mappoint installation mounted on a linux folder? or do this COM interface need to execute on windows necesarylly?