Failed: Three versions of Office Communications Server R2 and Lync were found. This configuration isn't supported. Please ...

Failed: Three versions of Office Communications Server R2 and Lync were found. This configuration isn't supported. Please complete the migration from Office Communications Server 2007 R2 to Lync Server 2010 or remove Lync Server 2010 before deploying Lync Server 2013. For help, see the Actions pane on the right.