I just followed the instructions for installing Webwork. Everything is working except for emailing he instructor. When a student attempts to email instructor the attached error pops up. Even though the error pops up, the email does go through and looks right. I checked to make sure I was using the latest Mail:Sender using the module checker and it appears I am. I went into the site.config file. I tried making $mail{smtpSender} = webwork@server.domain.edu, webwork@domain.edu and even my own email address. It does not seem to make a difference.
Using email to email the entire class does not cause the error.
Any help would be appreciated. I want students to use email and I don't want them to have any excuses.
John