Calendar keeps losing custom event to launch a program. Is this a bug? I had a daily event set up in calendar that runs a particular program.  Recently it stopped running this (possibly after an upgrade?).  Took me a few days or weeks to notice (because it happens automatically).  I go into the event and see no alert is set.

I create a new event and add my custom alert to open a file that is a program:




and then when I click back into the event I can see that no alert is present!



Is this a new bug or am I doing something wrong?

I am on OSX El Capitan 10.11.5 and Calendar Version 8.0 (2092.3).
You are using a calendar that is connected to iCloud. Since iCloud calendars do not support file opening events, it cannot save to iCloud and then it cancels. Make a new LOCAL calendar that is not on iCloud but based on your own computer, then you can do a file based event on the computer based calendar.