DIERR_ALREADYINITIALIZED

Undocumented in source but is binding to Windows. You might be able to learn more by searching the web for its name.
extern (Windows) @nogc nothrow __gshared
enum DIERR_ALREADYINITIALIZED = MAKE_HRESULT(SEVERITY_ERROR, FACILITY_WIN32, ERROR_ALREADY_INITIALIZED);

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