We recently upgraded our Exchange 2007 to Exchange 2013. (Separate server)
The Exchange 2007 server is still part of the installation.
I assume all the roles were transferred correctly. Switching off the Exchange 2007 server, Exchange 2013 seems to be functioning as expected.
I am in the process of removing Exchange 2007 from the installation. Is there a single-test or check that I can run to confirm that all functionality is now residing with Exchange 2013? (We can't afford any downtime after the removal)