Workflow error on sending email

Good afternoon,



I request your support in understanding and resolving the following situation.

I have the following enviro:

 - Sharepoint Server 2013

 - Workflow 1.0

 - MS Server 2008 R2 Standard (with memory problems)

 - Web Marshall

All installed and properly configured (so I say).

I created a workflow that is supposed to send an email when new events are created on my Calendar. 

I don't understand the log much, but I didn't identify anything that pertains to an error on email or workflow itself. If there is a specific term (besides 'workflow') that I must search on the log file, may you please tell me?

I thought that maybe the email configuration wasn't done correctly, but I tested an alert and received an email, so email config is not the problem.

So I go to Event Viewer and I get this message:

------------------------------ E.V. -------------------------------------------

Service Bus exception swallowed at location ServiceBusNamespaceListener.GetSessionAndStateWithRetryAsyncResult.HandleException. System.UnauthorizedAccessException: The token provider was unable to provide a security token while accessing 'https:/ /(server name):9355 /WorkflowDefaultNamespace/$STS/Windows/'. Token provider returned message: (HTML code for a page that says that my user was not authenticated/access denied)
------------------------------ E.V. -------------------------------------------

The user I created is (domain)\sharepoint. Why is it being intercepted by my Web Marshall? Could this be the reason the Workflow is not working?

SB and WF configuration was done using WF PowerShell and the registration with SP PowerShell. I also followed the article published by Margriet Bruggeman called 'SharePoint 2013 Best Practices Creating a Dev Environment: Configure Workflows'

May you please help me understand what could be making the Workflow not work? Did I miss any configuration, or maybe some part could be wrong?

Thank you for reading.

Regards,


Polyana