Tickets can be deleted under the following circumstances:

*: The Setup user can delete any ticket at any time.

*: If a ticket was created by anonymous within the previous 24 hours
   and has not been changed by any user other than anonymous, then
   registered users with the Delete privilege can delete the ticket.

*: Anonymous users can never delete a ticket, even if they have
   the Delete privilege.

To delete a ticket, select the [Edit] hyperlink.  A "Delete" button
will appear at the bottom of this page.  Press the button to go to
a confirmation screen.

The most recent change to a ticket can be undone under these
circumstances:

*: The Setup user can undo the last change at any time.

*: Registered users (users other than anonymous) can undo the
   last change if they are the person who made the last change
   and the change was made within the previous 24 hours.

*: Registered users with the Delete privilege can undo changes
   by the anonymous user that were made within the previous
   24 hours.

To undo a change to a ticket, view the ticket change history.  A
hyperlink in the history will allow the change to be undone.  There
is no confirmation screen when undoing a ticket change.  There is
no redo button.

See also: DeleteWiki and DeleteAttachment.