title: Exchange Server Transport Agent Won't Load, "Built By a Newer Runtime"
body: <p>I have built a simple transport agent (using .NET 4.0) for exchange 2010 and I'm trying to install it using the exchange management shell, but I run across this error:</p>
  
  <pre><code>Could not load file or assembly 'file:///C:\Program Files\Microsoft\Exchange Server\V14\Public\MySimpleAgent.
  dll' or one of its dependencies. This assembly is built by a runtime newer than the currently loaded runtime and cannot
   be loaded.
      + CategoryInfo          : InvalidArgument: (:) [Install-TransportAgent], BadImageFormatException
      + FullyQualifiedErrorId : 3A033BB9,Microsoft.Exchange.Management.AgentTasks.InstallTransportAgent
  </code></pre>
  
  <p>I really only found one good <a href="http://int.social.technet.microsoft.com/Forums/en-US/exchangesvrdevelopment/thread/4a326e90-1c3b-4ce9-9505-b0b9bf177813" rel="nofollow">public discussion</a> of this issue, but the solutions suggested by some have not helped my situation.</p>
  
  <p>I have:</p>
  
  <ul>
  <li>Made sure that my project references both <code>Microsoft.Exchange.Data.Transport</code> and <code>Microsoft.Exchange.Data.Common</code></li>
  <li>Deployed my assembly(ies) to <code>\Program Files\Microsoft\Exchange Server\V14\Public</code></li>
  </ul>
  
  <p>Any other suggestions?</p>