We are having a recurring problem where every few days all the events in the two higest groups (global and course) are rendered "invisible". Seems that all of a sudden they are all "invisible". We have to go into the database and run a SQL statement and mark them all is "visable", but then a few days later, sometimes in the same day, it happens again. It seems to happen about twice a month at least, once at the beginning of the month and once in the middle of the month, but the day is never the same.

I do remember that at one time we cleared out some fields in another table (mdl_course_sections). The fields were the "sequence" and "summary" fields. This was done when we needed to delete all content for the weeks for the year after we advanced the start dates for all the weeks. (We also added an extra week.) I wonder if that had anything to do with it. This is when we lost some parts of the site's main menu and possibly some main site content. At that time we basically went back to a back up we made and re-inserted the "sequence" numbers listed for the main site "course" and that fixed a whole bunch of stuff.

Any ideas. I've seen others report this problem, but I've seen no solution. See links below.

http://moodle.org/mod/forum/search.php?search=visible+events&id=5&perpage=10&page=1
Calendar -> Single user events disapeared -> Re: Single user events disapeared
posted by Mikael Ekblom

Calendar -> All events suddenly disappeared
posted by Samuli Karevaara

http://moodle.org/mod/forum/search.php?search=visible+events&id=5&perpage=10&page=3
Calendar -> Events not shown on site calendar
posted by Gustav W Delius

http://moodle.org/mod/forum/search.php?search=events+disappear&id=5
Calendar -> All manual added events disappeared -> Re: All manual added events disappeared
posted by Zachary B

checked for Moodle backups - not enabled
checked for MySQL backups - none set/enabled
checked for Windows Scheduled Tasks - none
went through system events list, found nothing

Thank you,
Bill Gonzalez