How Can I Delete A Data Row In C++ (MFC)

Hi,

i like to delete data. I can read and write into the database. But somehow i cant delete data from my Microsoft SQL Server. Always get error on CanUpdate().

Did i forgto something ???


CODE::::
void CListAllDlg::OnBnClickedDelete()
{
CDatabase db;
CProducts m_pData(&db);
CString m_ListItem="";
int nItem=0;

POSITION pos = m_list_all.GetFirstSelectedItemPosition();

//open Recordset
if(m_pData.Open()==0)
{
AfxMessageBox("Datenbank Verbindung fehlgeschlagen", IDOK);
return;
}
if (MessageBox("Möchten Sie diesen Datensatz wirklich löschen?","Datensatz löschen", MB_YESNO | MB_ICONQUESTION) == IDYES)
{
do
{
m_ListItem = m_list_all.GetItemText(nItem,1);
//delete data
while(!m_pData.IsEOF())
{
//found data then delete
if(strcmp(m_pData.m_articel,m_ListItem)==0)
{

m_pData.Delete(); //delete data in database
m_pData.Update(); //confirm & update database
nItem = m_list_all.GetNextSelectedItem(pos);
m_list_all.DeleteItem(nItem); //delete data in listbox
MessageBox("Datensatz wurde erfolgreich gelöscht","Datensatz löschen", MB_OK);
}
m_pData.MoveNext();
}//end while
}while (pos != NULL);
m_pData.Close();
}//end if
}//end OnBnClickedDelete