title: Loading an external DLL into Blazor from local machine
body: <p>I am trying to load assembly to Blazor application on runtime as illustrated <a href="https://github.com/dotnet/aspnetcore/issues/15878" rel="nofollow noreferrer">here</a>.</p>
  <p>However I am getting an error while trying to load the assembly in <code>OnInitializedAsync()</code>:</p>
  <blockquote>
  <p>Microsoft.AspNetCore.Components.WebAssembly.Rendering.WebAssemblyRenderer[100]
  Unhandled exception rendering component: Response status code does not
  indicate success: 404 (Not Found).
  System.Net.Http.HttpRequestException: Response status code does not
  indicate success: 404 (Not Found). at
  System.Net.Http.HttpResponseMessage.EnsureSuccessStatusCode ()
  &lt;0x3dd2d10 + 0x00052&gt; in :0
  at System.Net.Http.HttpClient.GetByteArrayAsyncCore
  (System.Threading.Tasks.Task<code>1[TResult] getTask) &lt;0x61d5a18 + 0x0010e&gt; in &lt;filename unknown&gt;:0   at WebAssembly.Client.Pages.Compiler.GetDlltoBrowser (System.Collections.Generic.List</code>1[T] references) [0x0008f] in
  C:\Users\User\source\repos\CInteractiveShell-Sample\WebAssembly\Client\Pages\Compiler.razor:200
  at WebAssembly.Client.Pages.Compiler.OnInitializedAsync () [0x00240]
  in C:\Users\User\source\repos\CInteractiveShell-Sample\WebAssembly\Client\Pages\Compiler.razor:47
  at Microsoft.AspNetCore.Components.ComponentBase.RunInitAndSetParametersAsync
  () &lt;0x37a0328 + 0x0013a&gt; in :0  at
  Microsoft.AspNetCore.Components.RenderTree.Renderer.GetErrorHandledTask
  (System.Threading.Tasks.Task taskToHandle) &lt;0x3cdd890 + 0x000b6&gt; in
  :0</p>
  </blockquote>
  <p>My Package references are:</p>
  <pre><code>&lt;PackageReference Include=&quot;Microsoft.AspNetCore.Components.WebAssembly&quot; Version=&quot;3.2.1&quot; /&gt;
  &lt;PackageReference Include=&quot;Microsoft.AspNetCore.Components.WebAssembly.Build&quot; Version=&quot;3.2.1&quot; PrivateAssets=&quot;all&quot; /&gt;
  &lt;PackageReference Include=&quot;Microsoft.AspNetCore.Components.WebAssembly.DevServer&quot; Version=&quot;3.2.1&quot; PrivateAssets=&quot;all&quot; /&gt;
  &lt;PackageReference Include=&quot;Microsoft.CodeAnalysis.CSharp.Scripting&quot; Version=&quot;3.7.0-4.final&quot; /&gt;
  &lt;PackageReference Include=&quot;System.Net.Http.Json&quot; Version=&quot;3.2.0&quot; /&gt;
  </code></pre>