> I run the reminders script every minutes, for half a dozen installs
That was meant to be "every minute", not "every minutes".

Kind of comparing apples to oranges, but I'm not seeing this behavior. 
  But, I'm running modified HEAD version of Kronolith, with a slightly 
modified reminder script [http://bugs.horde.org/ticket/?id=649], and 
using a SQL VFS backend.  I run the reminders script every minutes, 
for half a dozen installs and am only receiving one reminder per event.

I am running the reminder script as root, which should have write 
access to any area of the OS.

I believ I am using "files on local system" as the VFS backend and 
/tmp as the directory. (These are pulled from my Horde preferences 
under administration)



Is there something I'm missing here?

Run the reminder script as a user that can write to the VFS. It stores 
this kind of state.

Current reminder system generates scads of email reminders due to the 
code  in function listAlarms($date) contained in 
horde/kronolith/lib/Driver/sql.php



The current code seems to add the event to the alarm list for the 
following code:-

if ($start->compareDateTime($date) <= 0 &&

                     $date->compareDateTime($event->end) <= -1) {

                     $events[] = $eventId;

                 }



So if we are running our reminder script every 15 minutes from cron 
and our meeting we have scheduled is  2 hours long, we keep getting 
emails to remind us about the meeting until the meeting is over which 
ends up being about 9 emails. If we run the reminders from cron every 
5 minutes (which is not unreasonable for a work environment), we would 
get  about  25 emails.



I've tried playing with the code to limit this by only adding the 
alarm if the current time is start_time + or - the alarm time, which 
seems to work for my specific case of 15 minute alerts, but I can see 
how this would cause problems if the alarm time was 2days before.



What is required, I believe, is a method to turn off the alarm after 
it has been sent or at least register the fact that this alert has 
been sent. I'm just not too sure how or  where the best place to 
tackle this is.



Either add another field to indicate that alarm has been sent or  turn 
off the alarm after the alarm has been sent. (I suspect this may cause 
problems with recurring events which have alarms.)