If you proceed with the removal of Exchange Server, data loss may result.

When trying to uninstall an Exchange 2013 Server we built recently, we receive the following message;

Warning:
There are messages waiting in the following queues: "servername\Shadow\4". If you proceed with the removal of Exchange Server, data loss may result.


What's the best way to turn off the services and stop email from being funneled thru this particular server so that the queue can be clear and we can uninstall Exchange?

Note: We built this Exchange 2013 server on "Windows Server 2012 R2" where my other Exchange servers are just "Windows Server 2012", so it cannot be joined to the DAG. So I need to rebuild...

Thanks in advance.