Copy DataGridView's rows into another DataGridView

So basically I've got 2 DataGridView and I need to copy the rows from one to the other.

So far I've tried:

DataGridViewRowCollection tmpRowCollection = DataGridView1.Rows;

DataGridViewRow[] tmpRowArray = new DataGridViewRow[tmpRowCollection.Count];
tmpRowCollection.CopyTo(tmpRowArray, 0);            

DataGridView2.Rows.AddRange((DataGridViewRow[]) tmpRowArray));

But it keeps saying that

"Row provided already belongs to a DataGridView control."

So what's the best way to copy the content of the rows (both DataGridView have the same columns) ?