Summary
After editing an Excel `.xlsx` file using Telerik RadSpreadsheet and saving it via the default Save option, the saved file becomes corrupted. It no longer opens in RadSpreadsheet (throws an error) and shows a repair warning in Microsoft Excel.
Reproduction Steps
1. Upload an Excel `.xlsx` file to the `ABC` folder on the server.
2. Load the file in RadSpreadsheet via a basic viewer page.
3. Make any small edit (e.g., change a cell’s value).
4. Click the built-in Save option in the RadSpreadsheet toolbar.
5. Attempt to:
- Reopen the saved file in RadSpreadsheet → Error: Object reference not set to an instance of an object.
- Open in Excel → Warning: “We found a problem with some content in ‘filename’. Do you want us to try to recover as much as we can?”
Files Attached
- `Original.xlsx` — Before editing, opens fine in both RadSpreadsheet and Excel.
- `Modified.xlsx` — After saving via RadSpreadsheet, causes errors.
- Screenshot of:
- RadSpreadsheet error :
- Excel repair prompt
Code Snippet :
<telerik:RadSpreadsheet ID="sample" runat="server" Visible="false" style="font-size: 10px;" />
protected void Page_Load(object sender, EventArgs e)
{
string fileName = (string)Session["SelectedFileName"];
SheetLoad(fileName);
}
private void SheetLoad(string fileName)
{
try
{
string filePath = Server.MapPath("~/ABC/" + fileName);
if (!File.Exists(filePath))
{
string errorMsg = "File not found: " + filePath;
ClientScript.RegisterStartupScript(this.GetType(), "alert", "alert('File not found!');", true);
return;
}
// Load spreadsheet using Telerik document provider
sample.Provider = new SpreadsheetDocumentProvider(filePath);
sample.Visible = true;
}
catch (Exception ex)
{
string errorMsg = "Error opening file: " + ex.Message + " | File: " + fileName;
ClientScript.RegisterStartupScript(this.GetType(), "alert", "alert('Error loading file!');", true);
}
}
**Observation:**
* This only happens for **some files**, especially ones that likely contain advanced Excel features.
* Other simpler files save and reload without any issue.
**Assumption:**
It seems the default save behavior of RadSpreadsheet is **not preserving some Excel structures**, leading to file corruption on save.
Dear Telerik Support. I found another bug related to this one below.
This line of code also causes the same issue.
$find("txtYear").clear();
See attached Console debug output.
It is my opinion that a hot fix needs to be done asap! The work around that Derek posted on May 23rd falls short of the bigger issue. This is a serious matter and needs to be addressed immediately.
Hello -
I just updated my components to 2025.1.218, and am receiving the following ADA Compliance issues on a page scan. This is to conform to WCAG 2.1 AA. The component is the Ajax telerik:RadComboBox:
Buttons must have discernible text
<button class="rcbActionButton" tabindex="-1" type="button">select</button>
Form elements must have labels
<input name="ctl00$MainContent$ComboBox$NewCombo" type="text" class="rcbInput radPreventDecorate rcbEmptyMessage" id="ctl00_MainContent_ComboBox_NewCombo_Input" value="Search..." autocomplete="off"></input>
Component in .ascx file:
EmptyMessage="Search..."
AllowCustomText="true"
MarkFirstMatch="true"
Skin="Bootstrap"
AutoPostBack="true"
SelectMethod="GetInfo"
DataValueField="Id"
DataTextField="Name"
OnSelectedIndexChanged="ComboBox_SelectedIndexChanged"
MaxHeight="250px" aria-labelledby="InfoLabel" />
Please advise. Thanks!
When pasting bullet lists from Microsoft Word into the editor, extra leading spaces ( ) appear in the list items. This causes unexpected indentation and formatting issues.
Before 2025 Q1
In 2025 Q1
Upgrading Telerik UI for ASP.NET AJAX to version 2025 Q1 (2025.1.211) throw a JavaScript error:
- Uncaught TypeError: Cannot read properties of undefined (reading 'parentElement')
Steps to reproduce: Have a RadWindow with NavigateUrl set to a different page:
<telerik:RadWindow ID="RadWindow1" runat="server" RenderMode="Classic" VisibleOnPageLoad="true" NavigateUrl="Default.aspx">
</telerik:RadWindow>
Hello,
Sometimes the context menu isn't positioned correctly when it pops up for the first time, or after you scroll the page or do a browser zoom. I've attached an example reported by our tester. I've checked your technical support and have found this:
I've tried setting the render mode to Lightweight (originally set to Auto), but unfortunately no luck.
Is this something that is fixed in a later version of the editor, or do you have another fix/workaround?
Thank you in advance,
Gerald
Hello
I have an ASP.NET Ajax Telerik Solution (site) that has a web site project and a library project. The solution was developed almost 8 years ago and so far I've been able to upgrade telerik controls several times without any problem. Now, when I tried to upgrade the Telerik controls using the Upgrade Wizard Project only shows the class library as you can see in the attached picture.
To replicate this beahavior:
1. Create a new Telerik VB Webform Site
2. Add a Class Library Net Framework project to the solution.
3. Add a reference to Telerik.Web.UI to the Class Library project (optional).
4. Save and close solution.
5. Reopen it and run the Telerik Upgrade Wizard Project.
It only shows the Class Library project ...
When assigning multiple resources and percentages, the first item in list always goes back to 100%.
It saves back to UI correctly but as soon as you leave or refresh page it goes back to 100% on first item and that's what's saved in database.
The online demo has the same code but demo doesn't save at all to test.
See attached screen shots.
Bug report
It is not possible to print a PDF through the PDFViewer print tool on Desktop Chrome and Android Chrome.
Reproduction of the problem
Load PDFViewer Basic Usage demo and tap on Print tool - https://demos.telerik.com/aspnet-ajax/pdfviewer/overview/defaultcs.aspx
Current behavior
Android - "There was a problem printing the page. Please try again." - no preview
Windows - the Print dialog shows and closes automatically
Expected/desired behavior
Print preview is available, allowing you to find a printer and print
Hi Telerik,
Just a heads-up - some of the demo pages are generating errors:
Server Error in '/aspnet-ajax' Application.
Runtime Error
Description: An exception occurred while processing your request. Additionally, another exception occurred while executing the custom error page for the first exception. The request has been terminated.
I have found this on:
Dear staff I know this post
https://www.telerik.com/support/code-library/detecting-changes-to-the-radeditor
But in any case the component RadEditor have the method 'OnTextChanged' in the client side.
Probably, id it doesn't works, is better to remove it.
Thanks
Renato
Pasting plain text content from notepad or other text editor into the RadEditor control (design view) results in container HTML tags adding to the content and inline styles that make the text unreadable.
Content pasted:
Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut placerat orci nulla pellentesque dignissim enim sit. Diam quam nulla porttitor massa id neque. Ipsum suspendisse ultrices gravida dictum fusce ut. Sed odio morbi quis commodo odio aenean. Sed faucibus turpis in eu mi bibendum neque egestas congue. Sed pulvinar proin gravida hendrerit. Cras semper auctor neque vitae tempus. Nisi porta lorem mollis aliquam ut porttitor leo a diam. Quis vel eros donec ac odio tempor. Tellus in metus vulputate eu scelerisque felis imperdiet proin. Et ligula ullamcorper malesuada proin libero nunc consequat interdum. Neque viverra justo nec ultrices.
Result in RadEditor:
<div class="telerik_paste_container" style="border-width: 0px; position: absolute; overflow: hidden; margin: 0px; padding: 0px;">Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut placerat orci nulla pellentesque dignissim enim sit. Diam quam nulla porttitor massa id neque. Ipsum suspendisse ultrices gravida dictum fusce ut. Sed odio morbi quis commodo odio aenean. Sed faucibus turpis in eu mi bibendum neque egestas congue. Sed pulvinar proin gravida hendrerit. Cras semper auctor neque vitae tempus. Nisi porta lorem mollis aliquam ut porttitor leo a diam. Quis vel eros donec ac odio tempor. Tellus in metus vulputate eu scelerisque felis imperdiet proin. Et ligula ullamcorper malesuada proin libero nunc consequat interdum. Neque viverra justo nec ultrices.</div>
See accompanying screenshots.
The issue can be replicated with AutoCompleteBox demo: https://demos.telerik.com/aspnet-ajax/autocompletebox/examples/default/defaultcs.aspx
Set the SingleLineEntries property to "Enabled", and add a new Entry to the AutoCompleteBox. At this point, the page will scroll up and as a result hiding the AutoCompleteBox.
While changing the value from RadCombox, meaning firing the SelectedIndexChanged, I am getting the below error.
Exception information:
Exception type: NullReferenceException
Exception message: Object reference not set to an instance of an object.
at MDM.WebApplication.MyPendingActions.rgrid_ItemDataBound(Object sender, GridItemEventArgs e)
at Telerik.Web.UI.RadGrid.OnItemDataBound(GridItemEventArgs e)
at Telerik.Web.UI.GridCommandItem.SetupItem(Boolean dataBind, Object dataItem, GridColumn[] columns, ControlCollection rows)
at Telerik.Web.UI.GridTableView.CreateTopCommandItem(Boolean useDataSource, GridColumn[] copiedColumnSet, GridTHead thead)
at Telerik.Web.UI.GridTableView.CreateControlHierarchy(Boolean useDataSource)
at Telerik.Web.UI.GridTableView.CreateChildControls(IEnumerable dataSource, Boolean useDataSource)
at System.Web.UI.WebControls.CompositeDataBoundControl.PerformDataBinding(IEnumerable data)
at System.Web.UI.WebControls.DataBoundControl.OnDataSourceViewSelectCallback(IEnumerable data)
at Telerik.Web.UI.GridTableView.PerformSelect()
at Telerik.Web.UI.GridTableView.DataBind()
at Telerik.Web.UI.RadGrid.AutoDataBind(GridRebindReason rebindReason)
at Telerik.Web.UI.RadGrid.OnLoad(EventArgs e)
at System.Web.UI.Control.LoadRecursive()
at System.Web.UI.Control.LoadRecursive()
at System.Web.UI.Control.LoadRecursive()
at System.Web.UI.Control.LoadRecursive()
at System.Web.UI.Control.LoadRecursive()
at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint).
When trying on localhost SelectedIndexChanged of RadCombobox is getting fired and rgrid_NeedDataSource of RadGrid is not fired but when deployed on IIS, the scenario is opposite, SelectedIndexChanged is not fired but rgrid_NeedDataSource is getting fired.
Please help.
Also another thing, I wanted to understand how to use licenses.licx file in our project for telerik dll version 2013.1.314.45?