Set base path to current directory if ContentRootPath is null on hosting environment. This path is where AI would look for appsettings.json file for ikey, endpoint etc.

src/Microsoft.ApplicationInsights.AspNetCore/Extensions/DefaultApplicationInsightsServiceConfigureOptions.cs

@@ -2,6 +2,7 @@
 {
     using System.Diagnostics;
     using System.Globalization;
+    using System.IO;
     using Microsoft.ApplicationInsights.AspNetCore.Extensions;
     using Microsoft.Extensions.Configuration;
     using Microsoft.Extensions.DependencyInjection;
@@ -28,7 +29,7 @@
         public void Configure(ApplicationInsightsServiceOptions options)
         {
             var configBuilder = new ConfigurationBuilder()
-                .SetBasePath(this.hostingEnvironment.ContentRootPath)
+                .SetBasePath(this.hostingEnvironment.ContentRootPath??Directory.GetCurrentDirectory())
                 .AddJsonFile("appsettings.json", true)
                 .AddJsonFile(string.Format(CultureInfo.InvariantCulture,"appsettings.{0}.json", hostingEnvironment.EnvironmentName), true)
                 .AddEnvironmentVariables();