The line with the last alarm time for the task (for @gwa999, search for the same UID code) need to be removed. But making this cause the task can't be marked as completed when the alarm dialog appears.
I mean, the next time the alarm window will appear. And then, the problem will arise again (unless the fix arrives before next time)

thanks!

i guess i'll wait until a fix arrives.

Here's a brief explanation how the recurring tasks work:

The "DUE" property always defined the due date of the first instance of the task. This does not change even if you mark the task completed and Rainlendar shows the next due date in its UI. The current due date is calculated from the COMPLETED property which defines when the task was set to completed. So, the due date Rainlendar shows is the one which comes after the COMPLETED date.

The X-RAINLENDAR-LASTALARMACK defines when the alarm was dismissed the last time (this information is also stored to the alarms.ini file as anoob mentioned). You will only see the alarm if the X-RAINLENDAR-LASTALARMACK is set before the alarm time for the task's current due time.

When a recurring task is set completed the COMPLETED date is set to the current due date so that Rainlendar will start to show the next due date (or actually it is set to the previous due date from the current time but that's a minor detail). The X-RAINLENDAR-LASTALARMACK is also set so that you don't get the alarm for the completed task anymore. In the current build this was done just by increasing the last alarm ack time which caused the problem. In the next build the X-RAINLENDAR-LASTALARMACK will be set just before the alarm for the current due date should be shown which hopefully fixes the problem.

I'm not sure if this clarified things or made everything just more confusing but the thing to note is that even if the problem should be fixed in the next build it won't automatically affect the existing tasks which already have the X-RAINLENDAR-LASTALARMACK set to a future date. So, you need to set the task at least once to completed so that the ack time gets set to a proper value.

rainy,

thanks for the explanation. a little confusing as what goes on unless one sits down to really understand as to how all of the time tags are being used. and at this point i'm not going to try since it sounds like you have a fix figured out.

just for the record, i created 2 new daily recurring alarms yesterday to test this. since these were new tasks they both popped up the alarms as scheduled. for the first i left the alarm displayed but clicked on "Completed" from the task list. as 'anoob' (i think it was him) previously described the pop-up disappears but the task remains in the task list. clicking "Completed" a second time on the task list removes the item from the list.

for the second pop-up i dismissed the alarm pop-up first and then clicked on "Completed" in the task list. in this case the task was removed immediately.

for both cases the alarms reappeared in the task list for the next day (i.e. today). however, when the pop-up alarms should have displayed today neither did. so this confirms that this bug does not just pertain to just preexisting tasks but even to new tasks added.

sort of amazed that others have not seen this issue and reported it.

rainy,

it was reported that the bug fix in beta 112 fixed a different type of alarm bug. did that fix introduce the bug that i am now seeing (and presumably everyone else)? and if not, do you know when this bug crept in, not that it really matters? i know when i first started using Rainlendar that the recurring alarms did work because i use them pretty extensively for recurring tasks. and at some point the bug i am now seeing appeared. i just don't know exactly when since i usually only update the software for the official releases.

BTW, i asked for an enhancement regarding putting some sort of indicator in the task pop-up (i.e. when you hover over a task item). right now what shows up are the tags Due, Priority, and Status. i had suggested adding a new one called Recurrence where it would would list at least the time recurrence (i.e. Daily, Weekly, etc.). this would be extremely useful since i want to simply delete one-time alarm occurrences. however, for recurring tasks (and alarms) i want to do a "Completed" so that the task gets re-scheduled for the next time period. right now, if i am not familiar with how the task was set up (recurring vs. non-recurring) i always have to go into Edit to check.