Office Web Apps 2013 Service starts, then stops

Hello!

I have a SharePoint 2013 site running fine, and I want to add the Office Web Apps server to the environment.  The SP server is on a physical machine, and the Office Web Apps server is a VM.

The installation is OK, but the Office Web Apps Service will not start: 

The Sp server and the Office Web Apps VM server are on the same domain. 

Here is the Event Log error:

Source:  WACSM, Event ID: 0; Level Error

 Service cannot be started. System.InvalidOperationException: The farm settings are invalid, so the AgentManager cannot start successfully. at Microsoft.Office.Web.Environment.WacServer.AgentManager.AgentController.ValidateFarmSettings() at Microsoft.Office.Web.Environment.WacServer.AgentManager.AgentController.StartAgents() at Microsoft.Office.Web.Environment.WacServer.AgentManager.AgentManagerApplication.OnStart(String[] args) at System.ServiceProcess.ServiceBase.ServiceQueuedMainCallback(Object state)

Thanks!