After upgrading to 2.1.0

ERROR: Failed sending email to: "Tennessee Traditional Flies" with subject: "ALERT: Admin settings have been changed in "Tennessee Traditional Flies"" Could not instantiate mail function.

I suspect this may be related to the application running in my test environment on XAMPP.

Does anyone have any experience running Zencart on XAMPP who might have an idea what could be causing this error in Zencart 2.1.0?