I have successfully given quizzes and copied quizzes.  I've done the latter for students who require extra time for an exam, and/or students who are taking the exam at a different time (i.e. a make-up).  Yesterday I followed the EXACT same procedure as before.  However, the quiz that I set up to run today is appearing as "locked" to my student.  The site is published.  The quiz IS published.  The quiz is NOT locked on my end.  The time window is set up correctly.  The student is enrolled.  The student is attempting to take the quiz during the appropriate time period.  The quiz is not in a module.  I've tried publishing and un-publishing, locking and unlocking, deleting the quiz and re-importing -- nothing works.  

#bogus locked quiz message

#locked quiz error