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License Activation Errors and Warnings
Starting with the 2025 Q1 release, using Telerik UI for ASP.NET AJAX without a license or with an invalid license causes specific license warnings and errors. This article defines what an invalid license is, explains what is causing it, and describes the related license warnings and errors.
Invalid License
An invalid license can be caused by any of the following:
- Using an expired subscription license—subscription licenses expire at the end of the subscription term.
- Using a perpetual license for product versions released outside the validity period of your license.
- Using an expired trial license.
- A missing license for Telerik UI for ASP.NET AJAX.
- Not installing a license key in your application.
- Not updating the license key after renewing your Telerik UI for ASP.NET AJAX license.
License Warnings and Errors
When using Telerik UI for ASP.NET AJAX in a project with an expired or missing license, the Telerik.Licensing build task will indicate the following errors:
| Error or Condition | Message Code | Solution |
|---|---|---|
No license key is detected | TKL002 | Set up a license key to activate the UI controls and remove the error message. |
Invalid license key | TKL003 | Download a new license key and use it to activate the UI controls and remove the error message. |
Your perpetual license is invalid. | TKL102 | 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 license, then download a new license key and use it to activate the controls. | ||
| - Downgrade to a product version included in your perpetual license as indicated in the message. | ||
Your subscription license has expired. | TKL103, TKL104 | Renew your subscription and download a new license key. |
Your trial license has expired. | TKL105 | Purchase a commercial license to continue using the product. |
Your license is not valid for the detected product(s). | TKL101 | Review the purchase options for the listed products. Alternatively, remove the references to the listed packages from package.json. |
No Telerik or Kendo UI product references detected in project.v. | TKL001 | - If you use Telerik products and see this message, update the Telerik.Licensing package to version 1.4.9 or later. |
| - If you do not use Telerik products, remove the Telerik.Licensing NuGet reference from your project. |