title: TripleDESCryptoServiceProvider Specified key is not a valid size for this algorithm at 128 bytes?
body: <p>I'm trying to update my encrypt decrypt function from DES to TripleDES.
  However, when I try to increase my key and iv byte array size from 8 to 128:</p>
  
  <pre><code>byte[] key = new byte[128], iv = new byte[128];
  TripleDESCryptoServiceProvider des = new TripleDESCryptoServiceProvider();
  </code></pre>
  
  <p>Where 8 was used for DESCryptoServiceProvider and 128 is now used for TripleDESCryptoServiceProvider I always get the same error:</p>
  
  <pre><code>Specified key is not a valid size for this algorithm.
  </code></pre>
  
  <p>Even though my byte arrays are complete filled in.</p>
  
  <p>What am I doing wrong? Is there any requirement besides the length to allow my key and iv to be used to create an Encryptor?</p>