Hi,
try the following....
foreach (DataRow dc1 in Project_Group_qf_or_qg.Rows)
{
dtfinal.Rows.Add(dc1);
}.
or if you want to add a row at specified position
foreach (DataRow dc1 in Project_Group_qf_or_qg.Rows)
{
dtfinal.dsEmployee.Tables[0].Rows.InsertAt(dc1,inserting position);
}.
Hope this helps