Ciao, in effetti ho utilizzato questo sistema e mi da quanto desideravo, tuttavia, certamente a causa della mi inesperienza ni mi segnala l'errore @cor_breve campo non dichiarato...ti posto parte del codice
codice:
   
<script runat="server">
    
    Sub page_load(ByVal sender As Object, ByVal e As EventArgs)
       
        Dim conn As New SqlConnection("Data Source=10.10.10.3,1434\SQLEXPRESS;Initial Catalog=NOTPREL;User Id=mauri1961;Password=bussa1961")
        Dim command As New SqlCommand("select * from corsi where cor_breve=' " & Request.QueryString("lkcomm").ToString() & "'", conn)
        conn.Open()
        
        conn.Close()
        
    End Sub
    
    Protected Sub DetailsView1_DataBound(ByVal sender As Object, ByVal e As System.EventArgs)
        Dim DetailsView1 As DetailsView = DirectCast(sender, DetailsView)
        If DetailsView1.CurrentMode = DetailsViewMode.Edit OrElse DetailsView1.CurrentMode = DetailsViewMode.Insert Then


            'Replace the row and cell numbers with the appropriate ones for your DetailsView
            DirectCast(DetailsView1.Rows(5).Cells(1).Controls(0), TextBox).TextMode = TextBoxMode.MultiLine
        End If
    End Sub
        
</script>
 <asp:DetailsView ID="DetailsView1" runat="server"  Width="950px"                AutoGenerateRows="False" BackColor="White" BorderColor="Gray" 
               BorderStyle="Solid" BorderWidth="1px" CellPadding="3" 
               DataSourceID="SqlDataSource1" 
               style="margin-right: 2px; margin-left: 2px;" 
        DataKeyNames="cor_breve" Font-Names="arial" Font-Size="Large" 
                   
        HeaderText="VARIAZIONE CORSI " 
        CellSpacing="2" EnableModelValidation="True" DefaultMode="Edit" 
       GridLines="Horizontal"
                
  AutoGenerateEditButton="true"
  AutoGenerateDeleteButton="true"
  AutoGenerateInsertButton="true">
                <EditRowStyle BackColor="white" Font-Bold="True" ForeColor="black" />
               <Fields>
                       <asp:BoundField DataField="cor_breve" HeaderText="Codice corso" 
                       SortExpression="cor_breve" ReadOnly="True" > 
                       <ControlStyle Height="30px" Width="100px" />
                       <HeaderStyle Font-Bold="True" Font-Size="small" HorizontalAlign="Left" 
                           VerticalAlign="Top" />
                       <ItemStyle Width="50px" />
                       </asp:BoundField>
                         <asp:TemplateField HeaderText="Corso">
                    <HeaderStyle Font-Bold="True" Font-Size="medium" HorizontalAlign="Left" 
                           VerticalAlign="Top" />
                    <ItemTemplate>
                        <asp:Label ID="Label1" runat="server" Text='<%# Eval("cor_corso") %>'></asp:Label>
                    </ItemTemplate>
                    <EditItemTemplate>
                        <asp:TextBox ID="update" ClientIDMode="Static" TextMode="MultiLine" Text='<%# Eval("cor_corso") %>' Height="100px" Width="600px" runat="server"></asp:TextBox>
                    </EditItemTemplate>
                    <InsertItemTemplate>
                        <asp:TextBox ID="insert" ClientIDMode="Static" TextMode="MultiLine" Text="" Height="100px" runat="server"></asp:TextBox>
                    </InsertItemTemplate>
                </asp:TemplateField>

 <asp:TemplateField HeaderText="Testo Scheda">
                    <HeaderStyle Font-Bold="True" Font-Size="small" HorizontalAlign="Left" 
                           VerticalAlign="Top" />
                    <ItemTemplate>
                        <asp:Label ID="Label1" runat="server" Text='<%# Eval("cor_note") %>'></asp:Label>
                    </ItemTemplate>
                    <EditItemTemplate>
                        <asp:TextBox ID="update" ClientIDMode="Static" TextMode="MultiLine" Text='<%# Eval("cor_note") %>' Height="600px" Width="600px" runat="server"></asp:TextBox>
                    </EditItemTemplate>
                    <InsertItemTemplate>
                        <asp:TextBox ID="insert" ClientIDMode="Static" TextMode="MultiLine" Text="" Height="100px" runat="server"></asp:TextBox>
                    </InsertItemTemplate>
                </asp:TemplateField>
                         
                       
                     


                   
                            </Fields>
               <FooterStyle BackColor="white" ForeColor="#8C4510" />
               <HeaderStyle BackColor="white" Font-Bold="True" ForeColor="black" />
               <PagerStyle ForeColor="#8C4510" HorizontalAlign="Center" />
               <RowStyle BackColor="white" ForeColor="black"  />
           </asp:DetailsView>


            <asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="Data Source=10.10.10.3,1434\SQLEXPRESS;Initial Catalog=NOTPREL;User Id=mauri1961;Password=bussa1961" ProviderName="System.Data.SqlClient" 
               SelectCommand="SELECT * FROM [CORSI] WHERE ([cor_breve] = @cor_breve)" 
               UpdateCommand="UPDATE [corsi] SET [cor_corso] = @cor_corso, , [cor_note] = @cor_note
                       WHERE [cor_breve] = @cor_breve"> 
           
            <UpdateParameters>
                
                <asp:Parameter Name="@cor_breve" Type="String"/>
                <asp:Parameter Name="@cor_corso" Type="String" />
              
                <asp:Parameter Name="@cor_note" Type="String" />
             
            </UpdateParameters>
        </asp:SqlDataSource>
    <br />
..pre brevità ho evitato di mettere nel codice postato tutti i campi

grazie in anticipo... Maurizio