title: IdentityServer 3 returns invalid_client
body: <p>I am using IdentityServer3 with EF. I have API project and i want to authenticate its access using <code>access token</code>.
  So based on <a href="https://identityserver.github.io/Documentation/docsv2/overview/simplestOAuth.html" rel="nofollow noreferrer">sample</a> i have configured client ( for API project) in identity server as below</p>
  
  <p><strong>Client Properties</strong></p>
  
  <p><a href="https://i.stack.imgur.com/CLVzn.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/CLVzn.png" alt="enter image description here"></a></p>
  
  <p><strong>Client Secret</strong>
  <em>(Note whatever the text i put as secret value, the admin UI automatically convert it)</em></p>
  
  <p><a href="https://i.stack.imgur.com/v32ZY.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/v32ZY.png" alt="enter image description here"></a></p>
  
  <p><strong>Scope</strong>
  <a href="https://i.stack.imgur.com/x05d2.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/x05d2.png" alt="enter image description here"></a></p>
  
  <p>Then using POSTMAN i am trying get access token, but i always get <code>invalid_client</code> error
  <a href="https://i.stack.imgur.com/MaRrI.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/MaRrI.png" alt="enter image description here"></a></p>
  
  <p>I have also tried getting access token using C# code, but get the same error</p>
  
  <pre><code>    static TokenResponse GetClientToken()
      {
          var client = new TokenClient(
              "https://xxxxxxxx/connect/token",
              "A0AD7FB8-2881-484F-xxxxxxxxxxxxxxxxxx",
              "a84iThYxAA5eZpkIzt9xxxxxxxxxxxxxxxxxx");
  
          return client.RequestClientCredentialsAsync("api").Result;
      }
  </code></pre>
  
  <p><strong>Update 1</strong><br>
  Here is what i see in identity server's log</p>
  
  <p>2018-12-21 19:29:59.284 +00:00 [Information] Start token request<br>
  2018-12-21 19:29:59.301 +00:00 [Debug] Start client validation<br>
  2018-12-21 19:29:59.302 +00:00 [Debug] Start parsing Basic Authentication secret<br>
  2018-12-21 19:29:59.302 +00:00 [Debug] Start parsing for secret in post body<br>
  2018-12-21 19:29:59.304 +00:00 [Debug] Parser found secret: "PostBodySecretParser"<br>
  2018-12-21 19:29:59.304 +00:00 [Information] Secret id found: "A0AD7FB8-2881-484F-ABE0-xxxxxxxx"<br>
  2018-12-21 19:29:59.943 +00:00 [Debug] Skipping secret: no description, secret is not of type SharedSecret.<br>
  2018-12-21 19:29:59.943 +00:00 [Debug] No matching hashed secret found.<br>
  2018-12-21 19:29:59.943 +00:00 [Information] Secret validators could not validate secret<br>
  2018-12-21 19:29:59.944 +00:00 [Information] Client validation failed.<br>
  2018-12-21 19:29:59.945 +00:00 [Information] End token request<br>
  2018-12-21 19:29:59.946 +00:00 [Information] Returning error: invalid_client  </p>
  
  <p><strong>Update 2</strong><br>
  (The the secret value is updated than what i have posted earlier)
  <a href="https://i.stack.imgur.com/Na9Ga.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Na9Ga.png" alt="enter image description here"></a></p>