In the screenshot you have the Alert icon circled in red. Just two icons to the right (the " i " inside the circle) if you select that one in the popup menu the last option will be "About Tableau Server" which would reveal the version.
Typically Alerts are thrown for the case of failed extracts like you mention. There's also a "Data Driven Alert" feature that you can set on a viz but that was introduced with version 10.3.
But there are also "Email Health Alerts" that can be enabled. If you bring up the "Tableau Server Configuration" window and then look at the "Alerts and Subscriptions" tab to see if the appropriate checkboxes have been selected. Also, it might be worth a quick glance at the "SMTP Setup" tab to see if Tableau Server is pointing to a valid SMTP Server.
Thanks for your prompt answers, Mark-- Sure enough, I'm using 10.1.5 (so those data-driven alerts I've been wanting are out of reach without an upgrade).
All the best! --Michael