When you suddenly become unable to receive mail using an application that you have successfully used before, the problem is usually with the mail server on campus. The mail server may be "down" or you may have exceeded your disk space on the server. If you use IMAP mail, read on, otherwise contact the main help desk (515-HELP).
Setting IMAP Preferences
In IMAP land, you can delete a message so that it no longer appears in your mail window, but until you compact or purge the online folder, the mail remains in the folder on the server, ready to be retreived should you decide that you shouldn't have thrown that mail away after all. You can configure your mail program to permanently remove all deleted mail each time you exit your mail program ...
In Netscape, use Edit=>Preferences=>Mail and Newsgroups=>Disk Space to change how Netscape handles your messages.
In Outlook, use Tools=>Options=>Other=>General, and check the box that says "Empty the Deleted Items Folder Upon Exiting".
Cleaning Up IMAP Folders (Compacting/Purging Folders)
I prefer to keep my deleted messages for a while, just in case I need them back. In this case, I need to make sure to periodically clean out the deleted messages in the IMAP folders.
In Netscape, highlight the folder you wish to clean up, then select File=>Compact This Folder. The messages marked for deletion will be removed permanently.
In Outlook, select Edit=>Purge Deleted Messages.
Visit IMAP at N.C. State for more information on using IMAP mail.