Last Updated: 09 Apr 2019 15:06 by ADMIN

Documentation says Firefox should be ok with LastModifiedDate, but it's not.  It's consistently being set to 1/1/0001 12:00:00 AM, which is not useful.

Happens in any RadAsyncUpload example if you look at the value for LastModifiedDate in the AsyncUploadedFile objects.

Works fine in Chrome, Edge.  Fails in Firefox for Mac or Windows.

Last Updated: 10 Apr 2019 15:29 by ADMIN
Created by: Richa Chauhan
Comments: 2
Category: Grid
Type: Bug Report
Keyboard navigation does not work in Firefox 65.0.1

While attempting to implement Keyboard Navigation for one of our RadGrid controls, we discovered that this navigation (Arrow Up/Down and Page Up/Down) did not work correctly in Firefox (though it did within IE, Edge, and Chrome). We also tested the Firefox Keyboard Navigation within the Telerik Grid Demo Site, and experienced the same behavior. 

Issue can also be observed with the Grid - Keyboard Support demo using Firefox 65.0.1

Do you know how to resolve this issue, or of any workaround?

Thank you,

Last Updated: 29 Mar 2019 12:44 by ADMIN
Created by: Victor
Comments: 15
Category: Editor
Type: Bug Report


The RadEditor's Design View became unusable in the latest Chrome Beta version (Version 73.0.3683.27). It is still working correctly on the latest stable Chrome 72, so I'm not sure if it is a problem that needs to be resolved on Chrome's end, just figured it'll be helpful to send this in as well. 

The HTML view still works, but switching back to Design causes an exception (attached). This is also directly off of the demo page, so it doesn't look like implementation is a factor. 

Last Updated: 19 Mar 2019 14:19 by ADMIN


  1. Create a page with a basic Rad Editor, with HTML mode enabled
  2. Go into HTML Mode, add at least the following:
    <input type="number" />
  3. Go back to Design Mode
  4. Click on the numeric input

To See the Problem:

  1. In the console of the Browser's Developer Tools, get a reference to the Rad Editor
  2. Call its getSelectedElement() function
  3. In Chrome, the returned element will be a <body> tag (NOT GOOD)
  4. In Firefox, it will be an apparently random (maybe the first?) user-selectable element within the HTML (NOT GOOD)
  5. In IE11, it will be the numeric input (DESIRED)
  6. In Edge, it will be a <body> tag (NOT GOOD)
Last Updated: 28 Mar 2019 15:00 by ADMIN



RadWindow is not opening in Windows10 PC , ( IE 11 / Google Chrome)

Working in all windows 8 PCs 

Getting Error Script5009   'Telerik' is undefined script block  (37) (2,5) in the IE Console



Last Updated: 02 Oct 2019 14:33 by ADMIN
Exporting an empty RadGrid to XLSX or Biff with ExportSettings-ExportOnlyData="true" and Caption set, throws exception: Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index

Steps to reproduce:

RadGrid markup:

<telerik:RadGrid ID="RadGrid1" runat="server" AutoGenerateColumns="true"
    <ExportSettings ExportOnlyData="true">
        <Excel Format="Biff" />
    <MasterTableView Caption="My Personalized caption" CommandItemDisplay="Top">
        <CommandItemSettings ShowExportToExcelButton="true" />

C# - Code behind

protected void RadGrid1_NeedDataSource(object sender, GridNeedDataSourceEventArgs e)
    RadGrid1.DataSource = OrdersTable();
private DataTable OrdersTable()
    DataTable dt = new DataTable();
    dt.Columns.Add(new DataColumn("OrderID", typeof(int)));
    dt.Columns.Add(new DataColumn("OrderDate", typeof(DateTime)));
    dt.Columns.Add(new DataColumn("Freight", typeof(decimal)));
    dt.Columns.Add(new DataColumn("ShipName", typeof(string)));
    dt.Columns.Add(new DataColumn("ShipCountry", typeof(string)));
    dt.PrimaryKey = new DataColumn[] { dt.Columns["OrderID"] };
    return dt;
Last Updated: 11 Feb 2019 10:07 by ADMIN

I've been trying to upgrade an existing solution to use the latest release version (2019) of the Telerik UI for ASP.NET AJAX and have encountered a major problem with the 'Tool Provider', a technique which is significantly used in my solution.  This same error displays in your own Telerik Demo.  Details are:


Description of the issue

Having multiple RadEditors on the same page, and trying the property "ToolProviderID" (to reuse the same floating tool amongst the different editors on the same page), causes a "javascript exception" on the client side.

URL of the Demo (Telerik Website)

Exception description

Uncaught TypeError: R.get_canAcceptTrackChange is not a function at c.RadEditor._initializeToolProvider (RadEditor.js:8239) at c.RadEditor.initialize (RadEditor.js:8297) at c.RadEditor.endUpdate (Telerik.Web.UI.WebRe597d4b%3ab25378d2:6) at Sys._Application.endCreateComponents (Telerik.Web.UI.WebRe597d4b%3ab25378d2:6) at Sys.WebForms.PageRequestManager._scriptsLoadComplete (Telerik.Web.UI.WebRe97d4b%3ab25378d2:15) at Sys.WebForms.PageRequestManager.<anonymous> (Telerik.Web.UI.WebRe597d4b%3ab25378d2:6) at Telerik.Web.UI.WebRe597d4b%3ab25378d2:6 at Sys._ScriptLoader._loadScriptsInternal (Telerik.Web.UI.WebRe97d4b%3ab25378d2:15) at Sys._ScriptLoader._loadScriptsInternal (Telerik.Web.UI.WebRe97d4b%3ab25378d2:15) at Sys._ScriptLoader._loadScriptsInternal (Telerik.Web.UI.WebRe97d4b%3ab25378d2:15)

How to reproduce the error (on Telerik demo website)

    - Mark the checkbox at the bottom of the page and click on "Update":

(the error can be seem on console, pressing F12)

Error message happening in our system

RadEditor.js:8239 Uncaught TypeError: R.get_canAcceptTrackChange is not a function at c.RadEditor._initializeToolProvider (RadEditor.js:8239) at c.RadEditor.initialize (RadEditor.js:8297) at c.RadEditor.endUpdate (Telerik.Web.UI.WebRe597d4b%3ab25378d2:6) at Sys._Application.endCreateComponents (Telerik.Web.UI.WebRe597d4b%3ab25378d2:6) at Sys._Application._raiseInit (Telerik.Web.UI.WebRe597d4b%3ab25378d2:6) at Sys._Application.initialize (Telerik.Web.UI.WebRe597d4b%3ab25378d2:6) at b (Telerik.Web.UI.WebRe597d4b%3ab25378d2:6) at HTMLDocument.a (Telerik.Web.UI.WebRe597d4b%3ab25378d2:6)

Sample code, causing the issue (our system)

Refer the attached image.

Last Updated: 28 Jun 2019 08:52 by ADMIN

Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index

This error seems to happen if there is a GridTemplateColumn that has the Exportable property set to False.

Last Updated: 08 Mar 2019 10:04 by ADMIN

I am using Telerik.WEB.UI version: 2018.1.117.45 in my website. I am getting as issue in RADEditor control when I create a hyperlink within Editor. Right clicking on that hyperlink opens a context menu, when I click on properties from the context menu, it opens an 'Image Manager' instead of 'Hyperlink Manager'.

The issue is occurring only in IE 11, rest all the browsers are opening 'Hyperlink Manager'. Please advise.

Thank you

Last Updated: 02 Oct 2019 14:32 by ADMIN
Created by: Felix
Comments: 8
Category: Grid
Type: Bug Report


Since updating to the latest release of UI for ASP.NET AJAY the RadContextMenu of my RadGrid is misaligned at the right edge of the screen. Even in your sample when you open the context menu at the right side of the screen the context menu is nor aligned to the left (like it used to be).

Please ses the attached printscreen.

Kind regards

Last Updated: 08 Mar 2019 09:45 by ADMIN

There's a bug in the RadEditor WordListConverter convert method.  See the attached image for details.  Note that the variable z is initialized and treated as an array (a stack, actually, with its items being pushed in and popped out).  However, perhaps because of a naming scope failure in the js-minifier, the z variable is, under certain conditions, set equal to an HTMLCollection, so a subsequent z.push method call fails.

This sample Word document reproduces the error.  It is admittedly full of bad list formatting, because it began life as a PDF, but it does exercise the RadEditor code in a way that causes the problem.  Select and copy its content and paste it in the RadEditor demo page here:

Click OK to "clean" the pasted content and note that nothing appears because of the error shown in the attached image.

Verified in the latest Chrome and FF builds on Windows 10.

Last Updated: 13 May 2019 14:00 by ADMIN
Created by: Daniel
Comments: 4
Category: MultiColumnComboBox
Type: Feature Request
The new MultiColumnComboBox control does not have any server side events.  Can you provide the same server side event that you have for the ComboBox? 
Last Updated: 29 Jul 2019 11:29 by ADMIN
When the Map position is not on the top of the page, creating a new marker via the OnClick event argument location, the marker is not correctly positioned.
Last Updated: 20 Mar 2019 15:28 by ADMIN
Created by: MailUp Dev
Comments: 5
Category: UI for ASP.NET AJAX
Type: Bug Report
Using Firefox 64.0,  selecting an image doesn't appear the resizing handles which are located on each corner of the object
Last Updated: 29 Jan 2019 11:22 by ADMIN
Inconsistent Behavior of RadEditor with Ribbon Bar Toolbar for a different type of dropdown toolbar controls.

In RadEditor with Ribbon Bar Toolbar, there are two different types of drop-down control observed.

Type1 includes "Paste" and "Strip All Formatting" 
Type2 includes "Font Name", "Real font size", "Foreground Color", "Background Color", "Apply CSS Class", "Paragraph Style" and "Undo"

In RadEditor with Ribbon Bar Toolbar When "Type 1" Dropdown is opened or expanded and we click on any "Type 2" Dropdown then "Type 1" dropdown is still remain open or expand.

vice versa In RadEditor with Ribbon Bar Toolbar When "Type 2" Dropdown is opened or expanded and we click on any "Type 1" Dropdown then "Type 1" dropdown is still remain open or expand.
Last Updated: 20 Dec 2018 14:19 by ADMIN
Created by: Vinson
Comments: 1
Category: UI for ASP.NET AJAX
Type: Bug Report
When I try to replace a white space in RadEditor, it is able to replace the words at the first line. The second one and onwards are not able to replace.


1. Open 'Find And Replace' dialog.

2. Go to 'Replace' tab.

3. Enter a white space for 'Find' text box.

4. Enter any character or word for 'Replace With' text box.

5. Hit on 'Replace All' button.

Reproducible in content which contains table elements and in the live demo:
Last Updated: 20 Dec 2018 17:18 by ADMIN
After performing some tests with images using the RadEditor I have found that when selecting the class to apply in the image properties dialog, it will not let you clear the class. When choosing the clear class option from the drop down it does not change the class of the image it will keep the same class that is already applied from the drop down.
Last Updated: 12 Dec 2018 10:34 by ADMIN
Steps to reproduce:
1. Load on IE 11
2. Input two lines in the textarea
3.  Select the second line from right to left by holding the left mouse button and releasing it when the cursor is outside of the text area

4. Press button 'delete' from keyboard with multi select content 
=> result: Can not delete content

5. Press button 'backspace' from keyboard 
=> result: back from url....

The problem happens only in IE when there is a select element on the page and when the mouse goes outside the boundaries of the textarea.

Temporary fix:
       <telerik:RadFormDecorator RenderMode="Lightweight" ID="FormDecorator1" runat="server" DecoratedControls="all"></telerik:RadFormDecorator>
            Telerik.Web.UI.RadFormDecorator.prototype._selectBodyClickHandler = function (e) {

                var target =;

                //in chrome the A element is not focused by default
                if (! &&target && target.focus && target !== document.activeElement) {
                    try {
                    } catch (ex) { }

                if ($telerik.isTouchDevice) {
                    while (target.nodeType != 1 && target.nodeType != 9)
                        target = target.parentNode;

                //See if an optGroup label
                if (this._isSelectOptgroup(target)) {
                    //Do nothing

                //Check if clicked on a box
                var box = this._getDecoratedSelectBoxParent(target);

                if (box) {
                    if (this._isSelectElementDisabled(box) || box === target) return;
                    else this._optionClickHandler(e);
                    if (box.setActive && != "hidden") box.setActive();

                //Check if clicked on a select header
                var header = this._getDecoratedSelectHeaderParent(target);
                if (header) {
                    if (this._isSelectElementDisabled(header)) return;
                    else this._expandHeader(header);

                    if (header.setActive) header.setActive();
                    if (header.focus) header.focus();

                //else - just hide the popup
Last Updated: 11 Feb 2019 10:08 by ADMIN
Created by: Rumen
Comments: 3
Category: UI for ASP.NET AJAX
Type: Bug Report
I'm using couple of Rad Editor controls in my webpart and using ToolProviderID for performance optimization.
I'm initializing one rad editor toolbar from server side and using the same toolbar to provide other rad editors with their toolbar, Bascially I'm using ToolProviderID attribute to initialize other RadEditors, after doing this the Comments and Track Changes feature stop working although their options are selected in the toolbar.

<telerik:RadEditor RenderMode="Lightweight" runat="server" ID="RadEditor1" EnableTrackChanges="true" EnableComments="true">
    <TrackChangesSettings Author="AuthorName" CanAcceptTrackChanges="true" UserCssId="reU0" />
            <telerik:EditorTool Name="AcceptTrackChange" />
            <telerik:EditorTool Name="RejectTrackChange" />
            <telerik:EditorTool Name="AcceptAllTrackChanges" />
            <telerik:EditorTool Name="RejectAllTrackChanges" />
            <telerik:EditorTool Name="EnableTrackChangesOverride" />
<telerik:RadEditor ID="RadEditor2" runat="server" ToolProviderID="RadEditor1" EnableTrackChanges="true" EnableComments="true"></telerik:RadEditor>
<telerik:RadEditor ID="RadEditor3" runat="server" ToolProviderID="RadEditor1" EnableTrackChanges="true" EnableComments="true"></telerik:RadEditor>
Last Updated: 10 Dec 2018 11:51 by ADMIN
Created by: Rumen
Comments: 0
Category: Calendar
Type: Bug Report
Open a demo page and select Bootstrap skin. You will see that the right corners of the clock button are cutted down.

.RadPicker .rcSelect {
    border-top-right-radius: 4px !important;
    border-bottom-right-radius: 4px !important;