Existing Agent service will not start

I have an existing exchange 2013 server that has run the Appassure agent 5.4.3.106 for over a year.  Yesterday I upgraded the Exchange CU & rebooted the server.

Since that time, the Appassure agent will not start, generating events 15300,15301,15005.

I ran netstat –na | find “8006” & nothing is using the port.

I considered reinstalling the agent, but I’d like to know what the problem is first.