The University strongly recommends that you do not use the Out of Office Assistant to notify external contacts that you are "Out of the Office". This is because the option, when set, sends an email back to everybody who sends you an email. This has the potential to confirm the validity of your email address to "spammers" and thereby increasing the spam mail received by the University.
You can set Rules for the Out of Office message, enabling you to be selective and send emails to 'Inside my organization' which will only include members of staff, students, etc. of the University.