Some user reported this morning the inability to send messages to users. They received a common error,

Final-Recipient: RFC822; username@ups.edu
X-Actual-Recipient: RFC822; username@ups.edu
Action: failed
Status: 5.3.0
(reason: Can’t create output)

This error was the result of poor deactivation of the quotaing system. The quota system had been turned off, but not removed from the fstab file. When the system was rebooted yesterday, the quota system was re-enabled and locked account in excess of their time limit. This issue has been corrected.