Please see below "******" were error "Object referenece not set..." is happening:
Private Sub DataGrid1_UpdateCommand(ByVal source As Object, ByVal e As System.Web.UI.WebControls.DataGridCommandEventArgs) Handles DataGrid1.UpdateCommand
Dim key As String = DataGrid1.DataKeys(e.Item.ItemIndex).ToString()
Dim P3ActivityID As Integer, delivDesc As String
Dim tb As TextBox
tb = CType(e.Item.Cells(1).Controls(1), TextBox)
P3ActivityID = CStr(tb.Text)
tb = CType(e.Item.Cells(2).Controls(1), TextBox)
delivDesc = tb.Text
Dim r As dsGridDeliverables.WP_DeliverablesRow
r = DsGridDeliverables1.WP_Deliverables.FindByDeliverable_Number(key)
'******* @@ code errors at next line @@*******
r.Deliverable_Description() = delivDesc
r.Deliverable_Number() = P3ActivityID
OleDbDataAdapter1.Update(DsGridDeliverables1)
DataGrid1.DataBind()
DataGrid1.EditItemIndex = -1
DataGrid1.DataBind()
Private Sub DataGrid1_UpdateCommand(ByVal source As Object, ByVal e As System.Web.UI.WebControls.DataGridCommandEventArgs) Handles DataGrid1.UpdateCommand
Dim key As String = DataGrid1.DataKeys(e.Item.ItemIndex).ToString()
Dim P3ActivityID As Integer, delivDesc As String
Dim tb As TextBox
tb = CType(e.Item.Cells(1).Controls(1), TextBox)
P3ActivityID = CStr(tb.Text)
tb = CType(e.Item.Cells(2).Controls(1), TextBox)
delivDesc = tb.Text
Dim r As dsGridDeliverables.WP_DeliverablesRow
r = DsGridDeliverables1.WP_Deliverables.FindByDeliverable_Number(key)
'******* @@ code errors at next line @@*******
r.Deliverable_Description() = delivDesc
r.Deliverable_Number() = P3ActivityID
OleDbDataAdapter1.Update(DsGridDeliverables1)
DataGrid1.DataBind()
DataGrid1.EditItemIndex = -1
DataGrid1.DataBind()