The application named HTTPS://test113.onmicrosoft.com/FTP was not found in the tenant named test113.onmicrosoft.com
<p>I have to authenticate an application against Azure AD. I have created the web API and added it to the Azure AD application section. Changed the manifest file, created a web API and authenticated with the Azure AD and created a Windows form, containing the following code:</p>

<pre><code> private async void button1_Click(object sender, EventArgs e)
 {
    string authority = "https://login.windows.net/test113.onmicrosoft.com";
    string resourceURI = "https://test113.onmicrosoft.com/ftp";
    string clientID = "5177ef76-cbb4-43a8-a7d0-899d3e886b34";
    Uri returnURI = new Uri("http://keoftp");

    AuthenticationContext authContext =
        new AuthenticationContext(authority);
    AuthenticationResult authResult =
        authContext.AcquireToken(resourceURI, clientID, returnURI);

    string authHeader = authResult.CreateAuthorizationHeader();

    // don't do this in prod
    System.Net.ServicePointManager.ServerCertificateValidationCallback =
            ((s, c, c2, se) =&gt; true);

    HttpClient client = new HttpClient();
    HttpRequestMessage request =
        new HttpRequestMessage(HttpMethod.Get, "https://localhost:44300/api/tasks");
    request.Headers.TryAddWithoutValidation("Authorization", authHeader);
    var response = await client.SendAsync(request);
    string responseString = await response.Content.ReadAsStringAsync();
    MessageBox.Show(responseString);
}
</code></pre>

<p>I have got an exception:</p>

<blockquote>
  <p>An exception of type
  'Microsoft.IdentityModel.Clients.ActiveDirectory.AdalServiceException'
  occurred in Microsoft.IdentityModel.Clients.ActiveDirectory.dll but
  was not handled in user code</p>
  
  <p>Additional information: AADSTS50001: The application named
  <a href="https://test113.onmicrosoft.com/ftp" rel="noreferrer">https://test113.onmicrosoft.com/ftp</a> was not found in the tenant named
  test113.onmicrosoft.com. This can happen if the application has not
  been installed by the administrator of the tenant or consented to by
  any user in the tenant. You might have sent your authentication
  request to the wrong tenant.</p>
  
  <p>Trace ID: e782d60e-b861-46a3-b32b-f3df78396bd0 
  Correlation ID:
  b4809815-2755-4de1-bd1b-0221d74fd0f0 Timestamp: 2016-03-17 11:20:08Z</p>
</blockquote>