COSERVERINFO ServerInfo;

    ServerInfo.dwReserved1 = 0;
    ServerInfo.dwReserved2 = 0;
    ServerInfo.pAuthInfo = NULL;

    ServerInfo.pwszName = L"SERVER_NAME";

    MULTI_QI mq[1];
    mq[0].hr = S_OK;
    mq[0].pIID = &IID_IClassFactory;
    mq[0].pItf = NULL;

    hr = ::CoCreateInstanceEx(
        CLSID_POSCfgServer,
        NULL,
        CLSCTX_ALL,
        &ServerInfo,
        1,
        mq);

   if (!FAILED(pItf))
   {
       IMyInterface * pIMyInterface = NULL;
       hr = mq[0].pItf->CreateInstance(NULL, IID_IMyInterface, &pIMyInterface)
       ...
   }