I created an ASP.NET Core 8 Web API. I’m hosting it on IIS on a Windows 11 machine.

I also installed the core bundle for hosting on IIS.

The issue is, when I use integrated login, I am not able to connect to the database. I get a 500.3 error. The username is not recognised.

I’ve tried changing the pool identity to various such as service, network etc. Also various authentication values such as anonymous enabled/disabled. All variations. I just cannot use integrated login. Works fine if I test using Visual Studio and IIS Express.

Any guidance is much appreciated.