help me to complete this exercies <<<<

this is my exercises: http://www.mediafire.com/?sharekey=b27029c249f6b328b64026cfc0611236e04e75f6e8ebb871
an error occurred at menu "View/Enrollments" . i don't know why.
please fix it in my files and send mail to me.
email: [email protected]
thank a lot!