Users are allowed 100 gigabytes on the student E-mail system. E-mail should be used, accordance with the Appropriate Use Statement, for non-commercial and educational use only. The E-mail system does employ automated space restrictions.
It is a good practice to empty your Deleted Items folder regularly as items you delete still apply towards your space limit until they have been emptied from the Deleted Items folder. Also be sure to occasionally check your Sent Items folder as every message you send is retained there and also counts against your space limit until you delete it.
Remember, mailboxes usually get filled by one message with a large attachment, not by many small E-mails. If you are getting warning messages, check to see if you have sent or received a large attachment recently.
You can access your email account through the steps listed here.