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License Key Errors

This page provides solutions for license key errors that you may encounter while building UI for ASP.NET Core apps.

The deployment articles in this documentation provide general guidance and fundamentals. Telerik does not provide technical support for setting up CI/CD environments or application publishing infrastructure, except for questions about using Telerik license keys.

Basics

A Telerik license key error may occur in the following scenarios:

Missing license key.
Using an expired subscription license after the end of the subscription term.
Using a perpetual license with a product version that was released outside the validity period of your license.
Using an expired trial license.
Using an outdated license key after making renewals or purchases.
Using a license key that doesn't include Telerik UI for ASP.NET Core.
Using conflicting license keys in the same environment. For example, using one global license key and one in the app. Or, using a license key file together with an environment variable in CI/CD environment.
Mismatching versions of the Kendo.Mvc.dll and the Kendo UI JavaScript files referenced in the project.

Refer to the error messages below for specific tips.

Error Messages

No license key is detected
Invalid license key
License key is installed but the banner and watermark do not disappear
Your subscription license has expired
Your perpetual license is invalid
Your trial license has expired
Your license is not valid for the detected product(s)

No license key is detected

Install a license key file. If you already downloaded it, make sure it's saved at the right place.

Invalid license key

Follow the automatic or manual installation steps from scratch.

This is a known issue in version Telerik UI for ASP.NET Core 2025.1.211 in scenarios related to deferring the initialization of the components, and in editing scenarios.

The following workaround can be applied to remove the banner and watermark.

Go to the License Keys page in your Telerik account.
On the Progress® Kendo UI® for jQuery row, click the View key link in the SCRIPT KEY column.
Copy the JavaScript code snippet into a new file, for example, telerik-license.js.
Add the script file to your project, for example, in the wwwroot\js folder.
Add the file as a script reference right after the kendo.aspnetmvc.min.js reference or the Kendo UI scripts you are using.

html

<script src="https://kendo.cdn.telerik.com/2024.4.1112/kendo.all.min.js"></script>
<script src="https://kendo.cdn.telerik.com/2024.4.1112/kendo.aspnetmvc.min.js"></script>
<script src="~/js/telerik-license.js"></script>

<!-- Rest of the HTML -->

This issue can also be caused by referencing different versions of the Kendo.Mvc.dll and the required Kendo UI JavaScript files. Ensure that the Kendo.Mvc.dll and the required client-side resources referenced in the project have an identical version, for example, 2025.1.211.

Your subscription license has expired

Renew your subscribtion. Then, update your license key.

Your perpetual license is invalid

You are using a product version released outside the validity period of your perpetual license. To remove the error message, do either of the following:

Renew your subscribtion. Then, update your license key.
Downgrade your app to a Telerik UI for ASP.NET Core version that was released within the subscription period of your perpetual license.

Your trial license has expired

Purchase a commercial license to continue using Telerik UI for ASP.NET Core.

Your license is not valid for the detected product(s)

Review the purchase options for Telerik UI for ASP.NET Core. Then, update your license key.

Ensure that you have set up an environment variable by following the steps from the Use License Keys in CI/CD article.

Alternatively, if you have included the telerik-license.txt file into the project and the project is under source control, add the license file under source control as well.