What is the default sender for email notifications in the Pressero system?

If you do not have any email account information set in Preferences > General Settings > Email, and you're not overriding the default settings in Sites > Site Name > Settings > Email Notifications tab, the default email sender is sender@pressero.com.  Please note that if you do not set up your email account information in Preferences > General Settings > Email, you will not receive any responses your users send by choosing to reply to email notifications generated by the Pressero system.