On Button Click Protected Sub btnSubmit_Click(sender As Object, e As System.EventArgs) Handles btnSubmit.Click MsgBox("INSIDE") If SocialAuthUser.IsLoggedIn Then Dim accountId As Integer = BLL.getAccIDFromSocialAuthSession Dim AlbumID As Integer = BLL.createAndReturnNewAlbumId(txtStoryTitle.Text.Trim, "") Dim URL As String = BLL.getAlbumPicUrl(txtStoryTitle.Text.Trim) Dim dt As New DataTable dt.Columns.Add("PictureID") dt.Columns.Add("AccountID") dt.Columns.Add("AlbumID") dt.Columns.Add("URL") dt.Columns.Add("Thumbnail") dt.Columns.Add("Description") dt.Columns.Add("AlbumCover") dt.Columns.Add("Tags") dt.Columns.Add("Votes") dt.Columns.Add("Abused") dt.Columns.Add("isActive") Dim Row As DataRow Dim uniqueFileName As String = "" If Session("ID") Is Nothing Then lblMessage.Text = "You don't seem to have uploaded any pictures." Exit Sub Else **Dim FileCount As Integer = Request.Form(Request.Form.Count - 2)** Dim FileName, TargetName As String Try Dim Path As String = Server.MapPath(BLL.getAlbumPicUrl(txtStoryTitle.Text.Trim)) If Not IO.Directory.Exists(Path) Then IO.Directory.CreateDirectory(Path) End If Dim StartIndex As Integer Dim PicCount As Integer For i As Integer = 0 To Request.Form.Count - 1 If Request.Form(i).ToLower.Contains("jpg") Or Request.Form(i).ToLower.Contains("gif") Or Request.Form(i).ToLower.Contains("png") Then StartIndex = i + 1 Exit For End If Next For i As Integer = StartIndex To Request.Form.Count - 4 Step 3 FileName = Request.Form(i) '## If part here is not kaam ka..but still using it for worst case scenario If IO.File.Exists(Path & FileName) Then TargetName = Path & FileName 'MsgBox(TargetName & "--- 1") Dim j As Integer = 1 While IO.File.Exists(TargetName) TargetName = Path & IO.Path.GetFileNameWithoutExtension(FileName) & "(" & j & ")" & IO.Path.GetExtension(FileName) j += 1 End While Else uniqueFileName = Guid.NewGuid.ToString & "__" & FileName TargetName = Path & uniqueFileName End If IO.File.Move(Server.MapPath("~/TempUploads/" & Session("ID") & "/" & FileName), TargetName) PicCount += 1 Row = dt.NewRow() Row(1) = accountId Row(2) = AlbumID Row(3) = URL & uniqueFileName Row(4) = "" Row(5) = "No Desc" Row(6) = "False" Row(7) = "" Row(8) = "0" Row(9) = "0" Row(10) = "True" dt.Rows.Add(Row) Next If BLL.insertImagesIntoAlbum(dt) Then lblMessage.Text = PicCount & IIf(PicCount = 1, " Picture", " Pictures") & " Saved!" lblMessage.ForeColor = Drawing.Color.Black Dim db As SqlDatabase = Connection.connection Using cmd As DbCommand = db.GetSqlStringCommand("SELECT PictureID,URL FROM AlbumPictures WHERE AlbumID=@AlbumID AND AccountID=@AccountID") db.AddInParameter(cmd, "AlbumID", Data.DbType.Int32, AlbumID) db.AddInParameter(cmd, "AccountID", Data.DbType.Int32, accountId) Using ds As DataSet = db.ExecuteDataSet(cmd) If ds.Tables(0).Rows.Count > 0 Then ListView1.DataSource = ds.Tables(0) ListView1.DataBind() Else lblMessage.Text = "No Such Album Exists." End If End Using End Using 'WebNavigator.GoToResponseRedirect(WebNavigator.URLFor.ReturnUrl("~/Memories/SortImages.aspx?id=" & AlbumID)) Else 'TODO:we'll show some error msg End If Catch ex As Exception MsgBox(ex.Message) lblMessage.Text = "Oo Poop!!" End Try End If Else WebNavigator.GoToResponseRedirect(WebNavigator.URLFor.LoginWithReturnUrl("~/Memories/CreateAlbum.aspx")) Exit Sub End If End Sub The above code works fine.I have added an Update Panel in the page to avoid post back, But when i add the button click as a trigger <Triggers> <asp:AsyncPostBackTrigger ControlID="btnSubmit" /> </Triggers> in the update panel to avoid post back, i get the following error.This happens when i add the button click as a Trigger to the update panel.