unable to to set paper size in printer properties

[narsi.rao16]

void CMFCApplication2Dlg::TestFinal()
{
CPrintDialogEx dlg;

CString strPrinterName = _T("Microsoft Print to PDF");
const WORD nPaperA4 = DMPAPER_A4;

// Preserve old default printer
TCHAR szOldDefault[256] = { 0 };
DWORD dwSize = _countof(szOldDefault);
if (!::GetDefaultPrinter(szOldDefault, &dwSize)) szOldDefault[0] = '\0';
CString strOldDefault = szOldDefault;

// Set target printer temporarily
::SetDefaultPrinter(strPrinterName);

// Get DEVMODE / DEVNAMES
CPrintDialog tempDlg(FALSE);
if (!tempDlg.GetDefaults()) goto RestoreDefault;

dlg.m_pdex.hDevMode = tempDlg.m_pd.hDevMode;
dlg.m_pdex.hDevNames = tempDlg.m_pd.hDevNames;
tempDlg.m_pd.hDevMode = NULL;
tempDlg.m_pd.hDevNames = NULL;

// Set default paper to A4
DEVMODE* pDevMode = (DEVMODE*)::GlobalLock(dlg.m_pdex.hDevMode);
if (pDevMode)
{
	pDevMode->dmFields |= DM_PAPERSIZE;
	pDevMode->dmPaperSize = nPaperA4;
	::GlobalUnlock(dlg.m_pdex.hDevMode);
}

dlg.DoModal();

RestoreDefault:
if (!strOldDefault.IsEmpty())
::SetDefaultPrinter(strOldDefault);
}

hi All,

unable to to set paper size in printer properties UI windows print. can you please help me for the same