Kestrel: An anonymous request was received in between authentication handshake requests?

Question

I created an Kestrel Asp.Net core application and tried to host it on a Windows Server (server1). I launch the application using

Browsing http://server1:8008 on server1 works without any error.

However, when browsing http://server1:8008 on a remote machine, it gets the following error?

PS C:\Websites\Portal> .\Blazor.exe --urls http://server1:8008
info: Microsoft.Hosting.Lifetime[0]
      Now listening on: http://[::]:8008
info: Microsoft.Hosting.Lifetime[0]
      Application started. Press Ctrl+C to shut down.
info: Microsoft.Hosting.Lifetime[0]
      Hosting environment: Production
info: Microsoft.Hosting.Lifetime[0]
      Content root path: C:\Websites\Portal
warn: Microsoft.AspNetCore.HttpsPolicy.HttpsRedirectionMiddleware[3]
      Failed to determine the https port for redirect.
fail: Microsoft.AspNetCore.Authentication.Negotiate.NegotiateHandler[5]
      An exception occurred while processing the authentication request.
System.InvalidOperationException: An anonymous request was received in between authentication handshake requests.
   at Microsoft.AspNetCore.Authentication.Negotiate.NegotiateHandler.HandleRequestAsync()
fail: Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware[1]
      An unhandled exception has occurred while executing the request.
System.InvalidOperationException: An anonymous request was received in between authentication handshake requests.
   at Microsoft.AspNetCore.Authentication.Negotiate.NegotiateHandler.HandleRequestAsync()
   at Microsoft.AspNetCore.Authentication.Negotiate.NegotiateHandler.HandleRequestAsync()
   at Microsoft.AspNetCore.Authentication.AuthenticationMiddleware.Invoke(HttpContext context)
   at Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware.<Invoke>g__Awaited|6_0(ExceptionHandlerMiddleware midd
leware, HttpContext context, Task task)

Answer 1

A bit old, but, the correction for this....

You need to setup SPNs for your application. Once the proper SPN is in place, the issue should go away.