Error: Application startup exception: System.InvalidOperationException: Cannot resolve scoped service from root provider. Solution: There is a chance that you are trying to inject a Service into an Asp.Net Core 3.1 Middleware through a constructor. Instead of injecting a Service Interface through a Middleware Constructor, inject it through an invoke method/function like so: public async Task Invoke(HttpContext context, IAnalytics analytics) { //Then use your Service in here analytics.SomeFunction(); } The service will be available to the Application when the Service Container is loaded. Let me know if this solves your problem by leaving me a review below: You can comment without creating an account or just like this article is this helped solve your problem.