title: Oracle.DataAccess.Client.OracleException: Unable to enlist in a distributed transaction
body: <p>We are installing a new BizTalk Server 2016 environment and we are migrating an old application with <strong>WCF-Custom + OracleDBBinding</strong> Send Port, with <strong>useAmbientTransaction</strong> = true.</p>
  <p>In the old environment (BizTalk 2009) is working fine and in the new environment we are testing with the same destination Oracle and PL.</p>
  <p>In the new environment, we are receiving this error:</p>
  <blockquote>
  <p>Oracle.DataAccess.Client.OracleException: Unable to enlist in a distributed transaction</p>
  </blockquote>
  <p>If we set <strong>useAmbientTransaction</strong> = false, works fine.</p>
  <p>Oracle MTS Service is running.</p>
  <p>Any help?</p>
  <p><strong>Additional Edit</strong></p>
  <p>I have activated Oracle MTS traces and the error is:</p>
  <blockquote>
  <p>OCI_ERROR - 2048</p>
  <p>ORA-02048: attempt to begin distributed transaction without logging on</p>
  </blockquote>
  <p><strong>Additional Edit (2)</strong></p>
  <p>We uninstall the Oracle Client 12c and install Oracle Client 11g as the previous environment. Now works.</p>