Here's what to do when reminders stop working

[Marton]

Suddenly the tasks did not remind me anymore. The device turned on at the scheduled time but there was no notification popup or sound.
What I did was delete every task from the device, delete all the notifications related to TASKS.EXE with the tool found on this thread http://forum.xda-developers.com/showthread.php?t=280104, sync with Outlook and move the deleted tasks from the Deleted items folder to the main Tasks folder so they're back, and that's it. It's working again!
Hope the tip helps someone!

[Sallala]

And we pray hard, that the error doesn't repeat itself in the future?
Can't belive, that my PDA doesn't function as a PDA. Remindres is a basic feature isn't it?
(I have the same problem. I wil try this, thank you!)

[Sallala]

Thank you Marton!
I removed some notification with the tool you suggested, and my reminders are back :-)

There were lot of notifications with date before today. I just delete the first one or two, reset my device and the earlyer reminders are displayed, and I colud dissimiss.

[Marton]

I'm glad this worked for you as well, Sallala!
For me the problem was gone and I did not have to repeat the procedure, fortunately.
The reminders stopped working on a busy day when I added 8 tasks, and they started reminding and I postponed some of them, and an incoming call stopped me from discard some, so it crashed somehow and I had no more reminders.
I searched all over the forums and people suggested Memmaid to clean the notifications. I tried it but had no luck. I tried other tools as well (I remember one from Scarybear) but still no luck, so I manually did what I described on the first post and voilà

Cheers!

Marton