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SecurityTokenException: No token validator was found for the given token.

I have an ASP.NET Core application that is using WSFederation as authentication protocol. The application authenticates through our internal ADFS server where a corresponding Relying Party is configured. When attempting to authenticate, the ASP.NET Core application returns the following error message:

SecurityTokenException: No token validator was found for the given token.

Here is the full error page:

I had a look at the application configuration, but everything looked fine there:

The issue turned out to be related to the Relying Party configuration in ADFS. I had enabled token encryption there but this is not supported by the WSFederation middleware in ASP.NET Core.

Here is how to fix it:

  • Go to your ADFS server
  • Open ADFS Management
  • Go to Relying Parties and click on the Relying Party you want to configure
  • Go to the Encryption tab and click Remove to delete the existing certificate

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