Yes, sorry, that is what I meant. We have over 3,000 students. Thank you for the suggestions, our programmer is looking into the php settings.
Here is the errors I got when accessing the gradebook:
Fatal error: Maximum execution time of 300 seconds exceeded in C:\Bitnami\moodle-2.8.5-1\apps\moodle\htdocs\lib\dml\mysqli_native_moodle_database.php on line 973
Fatal error: Maximum execution time of 300 seconds exceeded in C:\Bitnami\moodle-2.8.5-1\apps\moodle\htdocs\lib\classes\shutdown_manager.php on line 67
We are considering upgrading to the newest version.