saludos, 
 
Este es mi codigo: 
Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btn_eliminar.Click
        If MsgBox("¿Está seguro de eliminar al usuario " & Me.txt_nombre.Text & "?", MsgBoxStyle.YesNo, "Administrador") = MsgBoxResult.Yes Then
            Try
                cn.ConnectionString = var_cn
                If cn.State = ConnectionState.Open Then
                    cn.Close()
                End If
                cn.Open()
                With cmd
                    .Connection = cn
                    .CommandType = CommandType.Text
                    .CommandText = "DELETE FROM USUARIO WHERE (usuario_usuario='" & Me.txt_usuario.Text & "');"
                    .ExecuteNonQuery()
                    limpiar_controles()
                End With
                cn.Close()
                Me.Response.Redirect("Default2.aspx")
            Catch ex As Exception
                Me.Label1.Text = "error" + ex.Message
            End Try
        Else
            Me.Response.Redirect("Default2.aspx")
        End If
    End Sub 
ya esta mi sitio levantado a traves del FTP, cuando doy clic en el boton eliminar se tiene que presentar un mensaje en un msgbox prguntando si estoy segura de eliminar dicho registro; pero en vez de eso se presenta este error: 
Server Error in '/pc' Application.
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Showing a modal dialog box or form when the application is not running in UserInteractive mode is not a valid operation. Specify the ServiceNotification or DefaultDesktopOnly style to display a notification from a service application. 
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.  
Exception Details: System.InvalidOperationException: Showing a modal dialog box or form when the application is not running in UserInteractive mode is not a valid operation. Specify the ServiceNotification or DefaultDesktopOnly style to display a notification from a service application. 
Source Error:  
An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.   
Stack Trace:   
[InvalidOperationException: Showing a modal dialog box or form when the application is not running in UserInteractive mode is not a valid operation. Specify the ServiceNotification or DefaultDesktopOnly style to display a notification from a service application.]
   System.Windows.Forms.MessageBox.ShowCore(IWin32Win  dow owner, String text, String caption, MessageBoxButtons buttons, MessageBoxIcon icon, MessageBoxDefaultButton defaultButton, MessageBoxOptions options, Boolean showHelp) +1801538
   System.Windows.Forms.MessageBox.Show(IWin32Window owner, String text, String caption, MessageBoxButtons buttons, MessageBoxIcon icon, MessageBoxDefaultButton defaultButton, MessageBoxOptions options) +26
   Microsoft.VisualBasic.Interaction.MsgBox(Object Prompt, MsgBoxStyle Buttons, Object Title) +544
   _administracion_mantenimiento_usuarios_default4.Bu  tton1_Click(Object sender, EventArgs e) +83
   System.Web.UI.WebControls.Button.OnClick(EventArgs e) +105
   System.Web.UI.WebControls.Button.RaisePostBackEven  t(String eventArgument) +107
   System.Web.UI.WebControls.Button.System.Web.UI.IPo  stBackEventHandler.RaisePostBackEvent(String eventArgument) +7
   System.Web.UI.Page.RaisePostBackEvent(IPostBackEve  ntHandler sourceControl, String eventArgument) +11
   System.Web.UI.Page.RaisePostBackEvent(NameValueCol  lection postData) +33
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +5102    
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Version Information: Microsoft .NET Framework Version:2.0.50727.42; ASP.NET Version:2.0.50727.210  
muchas gracias a quien pueda ayudarme, y tal vez corregirme el codigo que les muestro ahi!
