...you will never receive an out-of-the-blue email from ISU Extension IT staff requesting your password.
Do not respond to email which does not identify a specific person or persons (but just says 'iastate.edu support team' or 'ISU Extension support team' or some other general label), particularly if they are requesting secure information like your password or Social Security Number. Do not respond to email that comes from a non-iastate.edu address, but claims to require your iastate.edu password.
Neither EIT or ISU IT will ever ask you for your password in an email. No other organization you do business with should ever ask you for your password via email either.
When you receive messages like this, you can trash them.