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Troubleshooting Telerik NuGet

This article provides solutions to common issues that you may observe when working with the Telerik NuGet server and the NuGet packages that it provides.

Issue: The NuGet Package Takes Time to Install or Update on Visual Studio

The NuGet package takes a long time to install or update on Visual Studio. How to improve the installation and update times?


  • Disable the auto-sync in the _references.js file by modifying the following /// <autosync enabled="false" /> line.
  • You can also disconnect the project from the source control before running the Update Wizard.

Issue: Telerik NuGet Returns 401 Logon Failed after Password Change

After changing your Telerik password, you get [Telerik Nuget] The V2 feed at '...' returned an unexpected status code '401 Logon failed.' error in the NuGet Package Manager.


After changing your Telerik password, you must reset your credentials in the NuGet.config file. To do this, run the NuGet Sources Update -Name "" -Source "" -UserName "your login email" -Password "your new password" command.

The password must contain only ASCII characters.

As an alternative, you can reset your Telerik NuGet Feed credentials from the Windows Credentials Manager

Issue: Unable to load the service index for source

Make sure that the Telerik NuGet Feed is live at

Issue: Resetting Telerik NuGet Credentials

On Windows, if you enter and save wrong credentials for the Telerik NuGet or if you change your Telerik credentials, you will not have access to the desired NuGet packages. Before entering the correct user name and password, you must clear the saved credentials.

Solution 1: Resetting The Credentials in NuGet.config

Try resetting your credentials by using the approach suggested in the Telerik NuGet returns 401 Logon failed after password change. If the credentials are not updated, continue with Solution 2 below.

Solution 2: Windows Credentials Manager

Use the Windows Credentials Manager to remove the saved credentials:

  1. In Visual Studio navigate to Tools > NuGet Package Manager > Package Manager Settings. Select NuGet Package Manager, click Package Sources, and remove the listed Telerik NuGet package source.
  2. Close Visual Studio.
  3. Open the Windows Credentials Manager. To access it, navigate to Control Panel > User Accounts > Credential Manager.
  4. Click Windows Credentials.
  5. Remove the following saved credentials:
    • UI for ASP.NET Core Remove credentials from Windows Credential Manager
  6. Add the Telerik NuGet Feed again, and then enter the correct credentials. For more details, refer to the Installing with NuGet article.
  7. Verify the NuGet credentials by inspecting the NuGet.config file located in %AppData%\NuGet\NuGet.config
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