An unhandled exception occurred while processing the request.

AggregateException: One or more errors occurred. (One or more errors occurred. (The NPM script 'start' exited without indicating that the Angular CLI was listening for requests. The error output was: Der Befehl "npm" ist entweder falsch geschrieben oder

))

System.Threading.Tasks.Task<TResult>.GetResultCore(bool waitCompletionNotification)

InvalidOperationException: The NPM script 'start' exited without indicating that the Angular CLI was listening for requests. The error output was: Der Befehl "npm" ist entweder falsch geschrieben oder

Microsoft.AspNetCore.SpaServices.AngularCli.AngularCliMiddleware.StartAngularCliServerAsync(string sourcePath, string npmScriptName, ILogger logger)