title: How can I solve a "base64 invalid characters" error?
body: <p>When I m trying to convert the value1 to byte[] using the following code:</p>
  
  <pre><code>string value1 = "4rdHFh%2BHYoS8oLdVvbUzEVqB8Lvm7kSPnuwF0AAABYQ%3D";
  byte[] value2 = Convert.FromBase64String(value1);
  </code></pre>
  
  <p>Ι received an error that the string contents invalid base-64 characters...</p>
  
  <p>What's wrong?</p>
  
  <p>Thanks!</p>