Datagridview items not showing in Combobox.

If I put the code on the same form I have the Datagridview it is working. But if the put it on another form Datagridview items is now working.

   Private Sub frmUpdateStudent_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
        For i As Integer = 0 To frmRecords.DataGridView1.Rows.Count - 2
            ComboBox1.Items.Add(frmRecords.DataGridView1.Rows(i).Cells(0).Value)
        Next
    End Sub