How to click yes in dialog box

HWND GetOutlookAsDialog(void) {
    datastruct ds = {0};
    EnumWindows(GetOutlookAsDialogProc, (LPARAM)&ds);
    Save_ProcessID = ds.ProcessID;
    Save_HWND=ds.hWnd;
    return ds.hWnd;
}

//I need to modify this block below
void _stdcall Handle_Outlook_Prompts() {
    if (HWND hWnd = GetOutlookAsDialog()) {
        HWND Button_SaveAs = ::GetDlgItem(hWnd, IDYES);
        {
            HANDLE ProcessHandle_SaveAs = OpenProcess(SYNCHRONIZE, FALSE, Save_ProcessID);
            ::PostMessage(hWnd, WM_COMMAND, MAKEWPARAM(IDYES, BN_CLICKED), (LPARAM)Button_SaveAs);
            WaitForSingleObject(ProcessHandle_SaveAs, INFINITE);
            CloseHandle(ProcessHandle_SaveAs);
        }
    }
}