title: Export data from FOUNDRY to external source
body: <p>my aim is to export a dataset saved as a CSV in FOUNDRY to an external sftp server.</p>
  <p>I have created a source following the documentation but I keep on getting the error:</p>
  <pre><code>Could not load file listing
  
  The agent failed to execute this explorer command: com.palantir.magritte.plugin.sftp.SftpClientException:Borrowing connection for ls failed: 
  {exception message=UnknownHostKey: XXXXXXXXXXXXXXXX. RSA key fingerprint is XXXXXXXXXXXXXXXXXXXXXXX, path=/}
  </code></pre>
  <p>My YAML looks like:</p>
  <pre><code>type: magritte-sftp
  hostname: XXXX.XXXX.XXX.XXX.XXX
  port: 22
  username: XXXXXX
  password: '{{PASSWORD}}'
  rootDirectory: /
  </code></pre>