I have this task set to run once every 60 minutes. The first time it ran, it ran 5 times consecutively, in a period of about 5 minutes. I disabled the task, thinking that, perhaps, the system was running it every minute, instead of every hour. The messages did stop, I thought because of the disabling. But then, right on cue, at the one hour point, it fired off again - four more times. In looking at the history directly from the database, they ran about a minute or so apart, and each one set its "run next" field properly for an hour later.

In addition to the problem of this running four times at the top of the hour instead of just once, the fact that the task was disabled, but chose to run anyway is more than a little bit of a concern.

Any thoughts on this?

We're having the same exact problem, DNN 04.06.02. This is actually pretty scary for us because we have a custom scheduler item setup to bill/charge members of the site, and it runs once a day. When kicked off it fires quite a number of times, each iteration within seconds of the last, exactly as the previous posts point out.

At this point i'm too afraid to enable the task due to the unknown risk of duplicate charges even though we have checks in place. Single install, setup with about 50 portals, each portal under its own app pool.

Any ideas/suggestions would be more than greatly appreciated.

I completely agree - Something that wasnt thought of during development and testing.

My thought is that the process is spawned for each running app pool, but can't find any confirmation on that.