Boy! you seem to be getting all confused :-)

For a start, here is how you solve the compiile error on line 28. Please note that I am not even thinking about the semantics and/or logical correctness of the code, only looking at your compile error and heres a way to go about solving it.

// Attributes
private:
char m_szSubject[1024];
public:
void Subject(LPCTSTR subject) {
WideCharToMultiByte(CP_ACP,0,subject,-1, m_szSubject,1024, NULL, NULL);
m_message.lpszSubject = m_szSubject;
}

I hope you are getting the hang of it now....