Email Alert not being sent by Workflow

I want to start using Workflows to generate email alerts to some of my users. I have added the crontab job and I checked that cron is running. I have configured out going email and the test works. I have created a simple workflow that should send an email to my email account (the same one used for the email test), when a new Note is added to an Opportunity by the Administrator. Nothing happens!! What am I doing wrong?

Attached are the Workflow setting captured as a screenshot

Have you checked the process audit subpanel for your workflow? - this will tell you if the workflow is executing or failing

The Process Audit subpanel is empty. So I guess this means the workflow is not running but why? It is enabled.