Last Updated: 02 Mar 2021 10:19 by ADMIN
Scheduled for R2 2021

Getting these errors when trying to update spreadsheet cells. Uncaught TypeError: Cannot read property 'offsetWidth' of undefined

The issue is happening even on the demo component when editing a cell:

Workaround from Admin: 

Load the following script under the ScriptManager:

    if (kendo && kendo.spreadsheet && kendo.spreadsheet.SheetEditor) {
        kendo.spreadsheet.SheetEditor.fn.activate = function (options) {
            var viewElement = this.view.element, viewWidth, scrollerElement, scrollbarWidth;
            this._active = true;
            this._rect = options.rect;
            this._range = options.range;
            this.cellInput.activeCell = this.barInput.activeCell = this._range.topLeft();
            this.cellInput.activeSheet = this.barInput.activeSheet = this._range._sheet;
            if (viewElement) {
                viewWidth = viewElement.width();
                scrollerElement = viewElement.find('.' + kendo.spreadsheet.View.classNames.scroller)[0];
                scrollbarWidth = scrollerElement.offsetWidth - scrollerElement.clientWidth;
                this.cellInput.element.css('max-width', viewWidth - scrollbarWidth - this.cellInput.element.position().left + 'px');
            return this;


Last Updated: 25 Feb 2021 16:04 by ADMIN
Release 2021 R1 SP1

When the EnableConfigurationPanel is enabled for the PivotGrid and is being rendered without having data bound to it, the "System.NullReferenceException: Object reference not set to an instance of an object." exception will be thrown.


To replicate the problem, add the following PivotGrid declaration to the page without binding data to it:

<telerik:RadPivotGrid ID="RadPivotGrid1" runat="server" EnableConfigurationPanel="true">

Last Updated: 25 Feb 2021 16:00 by ADMIN
Release 2021 R1 SP1

By changing the application's thread Culture to Persian (fa-IR) and the Grid's RenderMode to Lightweight, the application fails with "System.ArgumentOutOfRangeException: Specified argument was out of the range of valid values."


To replicate the error


1. Change the application culture to Persian

protected void Page_Init(object sender, System.EventArgs e)
    var culture = new System.Globalization.CultureInfo("fa-IR");

    System.Threading.Thread.CurrentThread.CurrentCulture = culture;
    System.Threading.Thread.CurrentThread.CurrentUICulture = culture;


2. Change the RenderMode of the Grid to Lightweight

<telerik:RadGrid ID="RadGrid1" runat="server" RenderMode="Lightweight">



Last Updated: 19 Feb 2021 12:54 by ADMIN
Empty row is added for the filter item in the export file, even if the [FilteringItem].Visible is set to false.
Last Updated: 17 Feb 2021 09:34 by ADMIN
Release R1 2021 SP1
Created by: Vessy
Comments: 0
Category: UI for ASP.NET AJAX
Type: Bug Report
RadButton's focus state styling is missing in Bootstrap.

Steps to reproduce:
1. Open
2. Focus any of the first buttons using the Tab key
    Result: No focus styles are applied
    Expected: Follow the steps above in Sunset skin


        button.RadButton.rbButton:focus {
            box-shadow: 0 3px 5px rgba(0, 0, 0, 0.125) inset;

Last Updated: 16 Feb 2021 08:20 by ADMIN
Release R1 2021 SP1
Created by: Kees
Comments: 2
Category: Installer and VS Extensions
Type: Bug Report

In the web.config you can put parts of the config in separate files. This is useful when updating a web.config without overwriting installation specific settings.

In web.config:

<appSettings configSource="appSettings.config">

In appSettings.config:

<?xml version="1.0"?>

  <add key="PageInspector:ServerCodeMappingSupport" value="Disabled" />
  <add key="Telerik.Web.UI.StyleSheetFolders" value="~/Skins" />
  <add key="Telerik.EnableEmbeddedSkins" value="false" />
  <add key="Telerik.Skin" value="Kis3" />
  <add key="Telerik.ScriptManager.TelerikCdn" value="Enabled" />
  <add key="Telerik.StyleSheetManager.TelerikCdn" value="Disabled" />

But the upgrade wizard cannot handle this and modifies the web.config like this:

<appSettings configSource="appSettings.config">
  <add key="Telerik.ScriptManager.TelerikCdn" value="Disabled" />
  <add key="Telerik.StyleSheetManager.TelerikCdn" value="Disabled" /></appSettings>

Resulting in different errors.

It's easy te correct this, but it's a little annoying.. :-)

Last Updated: 15 Feb 2021 14:35 by ADMIN
Release R1 2020 SP1
We have an issue where the RadEditor context menu for <td> element doesn't get displayed. It throws a "Permission Denied" error. Within <td> the table toolbar is not functional either. 
To reproduce: In an aspx page, create an updatepanel with a LoadContent button, RadEditor and Save button.
1. Click on Load Contents button
2. RadEditor with text "Loaded" will get displayed
3. Insert a table
4. Go to a table cell and verify context menu for td shows fine
5. Click Save
6. Go to a table cell and right click - context menu doesn't show (If you have IE developers tool, you will see "Permission Denied" error.)

ASPx page:
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="server">
    <asp:UpdatePanel ID="upd" runat="server">
              <asp:Button ID="btnLoad" runat="server" Text="Load Contents"  OnClick="btnLoad_Click"  />
              <telerik:RadEditor ID="HTMLEditor" runat="server"></telerik:RadEditor>          
                <asp:Button ID="btnSave" runat="server" Text="Save"  OnClick="btnSave_Click" UseSubmitBehavior="false" />
C# Code:
 protected void Page_Load(object sender, EventArgs e)
        protected void btnSave_Click(object sender, EventArgs e)
            HTMLEditor.Content = HTMLEditor.Content + " updated";            
        protected void btnLoad_Click(object sender, EventArgs e)
            HTMLEditor.Content = "Loaded";
Last Updated: 12 Feb 2021 15:52 by ADMIN
Created by: Francesco
Comments: 1
Category: Grid
Type: Bug Report

Good morning,

we have a strange issue using RadGrid with horizontal scroll and frozen columns: there a resizing of the height which gets user experience not the best.

See attached gif.


Could you please help us?

Last Updated: 09 Feb 2021 19:23 by ADMIN
Created by: Steve Rothschild
Comments: 4
Category: Editor
Type: Bug Report
I recently updated my website with the dll patch telerik  provided for the cryptographic weakness:

After the update I found that the pages which were using the RadEditor control and several other controls was not loading and throwing this error:
Parser Error Message: Decryption key specified has invalid hex characters.

Several other controls are throwing this error but I cannot delete controls one by one and check which ones are having this problem.

But I checked for the RadEditor and it was throwing this error. Nothing else is there on the page while testing other than this control.
This does not happen on a plain new website and is happening when we have the sql mermbership and machine key configured. We are using passwordFormat as encrypted in sql membership config and cannot remove machine key.
If you got to test it, then test it on some already configured machine key and sql membership website.

I have attached screenshots for this error and telerik dll patch in use currently.

We are on a production server and we need a solution for this issue ASAP.
Last Updated: 08 Feb 2021 16:57 by ADMIN
<script runat="server">
    protected void RadGrid1_NeedDataSource(object sender, Telerik.Web.UI.GridNeedDataSourceEventArgs e)
        (sender as RadGrid).DataSource = Enumerable.Range(1, 10).Select(x => new { Id = x, Name = "Name " + x });

<telerik:RadFormDecorator ID="RadFormDecorator1" runat="server" DecorationZoneID="test" DecoratedControls="All" />
<div id="test">
    <telerik:RadGrid ID="RadGrid1" runat="server" OnNeedDataSource="RadGrid1_NeedDataSource" AutoGenerateColumns="true"
        EnableHeaderContextMenu="true" FilterType="HeaderContext">
Last Updated: 25 Jan 2021 09:46 by ADMIN
The horizontal scrollbar is not visible in iOS when the grid is empty.

Code to reproduce the problem:
        html, body, body > form {
            height: 100%;
            padding: 0;
            margin: 0;
        <telerik:RadGrid ID="RadGrid1" runat="server" AllowPaging="True" Width="100%"
                <Scrolling AllowScroll="true" />
            <MasterTableView Width="1500px">

    protected void RadGrid1_NeedDataSource(object sender, Telerik.Web.UI.GridNeedDataSourceEventArgs e)
        (sender as RadGrid).DataSource = GetData();

    private object GetData()
        DataTable dt = new DataTable();

        //dt.Rows.Add(1, 2, 3, 4, 5, 6, 7, 8);

        return dt;
Last Updated: 20 Jan 2021 13:45 by ADMIN

Reproduction -

Setup to reproduce:

<telerik:RadContextMenu ID="RadContextMenu1" runat="server">
        <telerik:ContextMenuDocumentTarget />
        <telerik:RadMenuItem Text="item">
                <asp:TextBox ID="TextBox2" runat="server" />

<telerik:RadButton runat="server" ID="RadButton2" Text="Postback" AutoPostBack="true" />

Steps to reproduce:

  • Show the context menu with a right mouse click on the document.
  • Type in a custom value in the TextBox embedded in the menu.
  • Perform a postback by clicking on the RadButton.
  • Show the context menu again. In the textbox, pick the autocomplete suggestion by the browser.
Last Updated: 12 Jan 2021 13:50 by ADMIN


<telerik:RadSpreadsheet runat="server" ID="RadSpreadsheet1" />
<telerik:RadSpreadsheet runat="server" ID="RadSpreadsheet2" />

protected void Page_Load(object sender, EventArgs e)
    var workbook = new Workbook();
    var sheet1 = workbook.AddSheet();


    sheet1.Columns = new List<Column>() { new Column() { Index = 1, Width = 150 } };


    RadSpreadsheet1.ColumnsCount = 5;
    RadSpreadsheet1.RowsCount = 10;

private void AddDateRow(Worksheet sheet1)
    var row = new Row() { Index = 0 };
    Cell firstCell = new Cell() { Index = 0, Value = "Select Date:", Bold = true };

    Cell secondCell = new Cell() { Index = 1, Value = "", Bold = true, Background = "#fef0cd", Format = "mmmm d, yyyy" };

    secondCell.Validation = new Validation()
        AllowNulls = true,
        DataType = "date",
        ShowButton = true,
        ComparerType = "between",
        From = "DATEVALUE(\"1/1/2000\")",
        To = "DATEVALUE(\"12/31/2020\")",
        Type = "reject",
        TitleTemplate = "Invalid date selected",
        MessageTemplate = "Select a date between year 2000 and 2020."






Last Updated: 12 Jan 2021 09:24 by ADMIN
To replicate use the following export settings for RadGrid:
    <Excel Format="Biff"  DefaultCellAlignment="NotSet"/>
Last Updated: 08 Jan 2021 09:43 by ADMIN
Created by: Stephen
Comments: 1
Category: ComboBox
Type: Bug Report
Given a RadComboBox with search, if the user enters some search text and then clicks on one of the filtered entries in the dropdown list the validation event is fired as the entry box loses focus and results in a 'false' return from validation as it uses the 'Text' property which is the search string. Validation is then refired as a result of clicking on the entry.
However, the initial 'false' return can cause unwanted behaviour in code that depends on the validation event.
I can supply a sample project demonstrating the problem, but it needs more than the 10 MB upload limit.
Last Updated: 06 Jan 2021 13:02 by ADMIN
Release R1 2021

Workaround(Approved by Admin):

    // Place/load this script after the ScriptManager
    if (Telerik.Web.UI.RadSpreadsheet) {
        Telerik.Web.UI.RadSpreadsheet.prototype.original_initialize = Telerik.Web.UI.RadSpreadsheet.prototype.initialize;
        Telerik.Web.UI.RadSpreadsheet.prototype.initialize = function () {
        Telerik.Web.UI.RadSpreadsheet.prototype.repaint = function () {


<telerik:RadWizard runat="server" ID="RadWizard1">
        <telerik:RadWizardStep ID="WizardStep1" StepType="Start">
            Step 1
        <telerik:RadWizardStep ID="WizardStep3">
            <telerik:RadSpreadsheet runat="server" ID="RadSpreadsheet1"></telerik:RadSpreadsheet>
        <telerik:RadWizardStep ID="WizardStep4" StepType="Finish">
            Finish step
        <telerik:RadWizardStep ID="WizardStep5" StepType="Complete">

Need More Info
Last Updated: 05 Jan 2021 14:42 by ADMIN
Created by: Doug
Comments: 1
Category: Installer and VS Extensions
Type: Bug Report


I got this dialog pop up when it was trying to upgrade my solution which had a few web sites in it.
It seemed to get lost. I dont know what the VS dialog with 'Description'  is all about.
Not sure what triggers it to say it needed an update and yet there is nothing to update.

Its possible that there is a backup folder that it created from a previous upgrade and it is looking at an old DLL in that project.

Anyway, sure you will sort it out :)




Last Updated: 04 Jan 2021 11:31 by ADMIN
When the RenderMode of RadGrid is set to Mobile and UniqueName is different from the DataField then trying to Ungroup an item, it throws an exception: Object reference not set to an instance of an object
Last Updated: 17 Dec 2020 18:54 by ADMIN
Put more than two RadDatePicker with single SharedCalendar on page. some RadDatePicker are in side of UpdatePanel with a button in it. when I press that button RadDatePicker behaviour is strange. 
RadDatePicker inside UpdatePanel not opening Calendar popup while RadDatePicker outside UpdatePanel opens calendar popup but gives javascript error on any date selection. the javascript error is "Unable to get property '_selectedDates' of undefined or null reference".
It looks like it is destroying shared calendar object on partial postback.
Please find below sample code to replicate the issue. after clicking "Submit" button, it doesn't open calendar popup for "Date 2" and for "Date 1" it opens but doesn't allow to select date and gives JavaScript error.

<asp:ScriptManager ID="sc1" runat="server" />
<telerik:RadCalendar ID="dtCal" runat="server" EnableMultiSelect="false" />
Date 1:
<telerik:RadDatePicker ID="dt1" Width="103px" runat="server" SharedCalendarID="dtCal" />
<hr />
<asp:UpdatePanel runat="server" ID="up">
		Date 2:
		<telerik:RadDatePicker ID="dt2" Width="103px" runat="server" SharedCalendarID="dtCal" />
		<br />
		<asp:Button runat="server" ID="btnDT" Text="Submit" />

When i add all controls in UpdatePanel it works properly. but Actual code is much more complex than above sample with too many lines of javascript code and many date pickers on single page and simply all Calendar and DatePicker controls can not be moved in UpdatePanel.
Last Updated: 15 Dec 2020 10:14 by ADMIN
Release R1 2021
Status bar in Grid does not hide after Exporting a document when OnCommand client event is handled
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