This article summarizes the issues that may occur when you work with the Telerik UI for Blazor library and the online Telerik private NuGet feed, and their solutions.
Regardless of the cause for the issue, it is recommended that you start from the section on the commonly occurring issues.
- Tips for handling common NuGet issues
- Removing stored credentials
Unable to find package
503 Service Unavailable
- Message about package
version not found
The most common reasons for issues with the private Telerik NuGet feed are related to:
- Authentication and credentials.
- Licensing. For example, requesting commercial packages with a trial license or vice-versa.
- Missing or wrong local configuration (
- Network connectivity issues, including proxies and firewalls.
Unable to load the service index for source https://nuget.telerik.com/v3/index.json don't indicate the exact cause of the problem. In such cases, check the additional error information which usually provides an error code.
To verify if you can access the Telerik NuGet server and the expected packages, open the https://nuget.telerik.com/v3/search?q=blazor&prerelease=true&skip=0&take=100&semVerLevel=2.0.0 URL directly in the web browser and enter your Telerik credentials in the prompt.
As a result, you will see a JSON output with the NuGet packages and versions that are available for you. Depending on your license, search for
If the above URL doesn't open, you have either come across a local networking issue or the NuGet server is down.
If you can access the feed in the browser, but you do not see the packages in Visual Studio, most likely the problem is caused by entering wrong credentials or using a different Telerik account. Make sure your saved credentials are correct. Also, you must not have a
NuGet.Config file in your project as it may bring in invalid credentials and project-level configuration files override the global ones.
If you suspect that your saved credentials are wrong, use the following steps to remove them from Windows and, then, add the correct ones:
- Remove the saved credentials in the Windows Credential Manager. These credentials will appear as
- Remove the Telerik NuGet package source from Visual Studio.
- If you have added the Telerik package source by NuGet CLI, try to remove it from the CLI by running the following commands:
- Check if you have any credentials stored in
%AppData%\NuGet\Nuget.Config. If so, remove them.
- Try to reset the Visual Studio user data by forcing NuGet to ask for authentication.
- Restart Visual Studio.
- Enter the Telerik NuGet package source again through Visual Studio or CLI. If you are using the feed in a .NET Core application, store your credentials as plain text.
If your credentials are correct and your license includes the requested product and version, then the password probably contains special characters. You need to escape these characters or the authentication can fail on the NuGet server. For example, a common character you must escape is the ampersand (
&); however, the character causing the issue may be as unique as the section character (
To solve the issue:
- Change the password so that it doesn't include characters you need to escape.
- Escape the special characters before storing the credentials. For example,
Avoid using an online encoder utility for a password. Instead, use a Powershell command:
Add-Type -AssemblyName System.Web [System.Web.HttpUtility]::HtmlEncode('my§uper&P@§§word')
If the error occurs for the
Telerik.UI.for.Blazor package, the Telerik NuGet source may not be added or enabled. The possible causes are:
- Missing configuration in the
- The correct
NuGet.Configfile is not used. This is common Docker scenario and the solution is to copy the
NuGet.Configfile (or configure the NuGet source) explicitly during the build. For more information, see the private NuGet feeds in Docker forum thread and some DevOps examples.
If the error occurs for the
Telerik.SvgIcons icon packages, the NuGet client is not using
nuget.org as a NuGet source. The possible causes are:
nuget.orgsource is disabled.
- There is
packageSourceMapping, which forces the NuGet client to search for the icon packages in the
nuget.telerik.comsource. However, the icon packages are published on
If you get a message like
Unable to load the service index for source and error
503 (Service unavailable), check the Telerik NuGet server health at the Telerik live services status page.
You may encounter an error similar to
ProjectName depends on Telerik.UI.for.Blazor (>= 3.6.1) but Telerik.UI.for.Blazor 3.6.1 was not found. An approximate best match of Telerik.UI.for.Blazor 3.7.0 was resolved.
This error means that version
3.6.1 is outside the subscription period of your license.
To solve the issue, use a different version or ask the license holder at your company to assign you another license that includes the desired product version.