Vista Disk Defragmenter and Task Scheduler and Un-scheduled Defrag Problem

About two weeks ago I deleted the Scheduled Task for Defrag as I could not get Defrag to work according to a once-a-week schedule.
I then created a new task for Defrag with a once-a-week schedule.

I notice now what is happening is Defrag is running two times per week. I have confirmed this issue by looking in my Task Scheduler History Tab, and viewing the Task Category that says Task Completed ie more than once inside of a week.

Help is appreciated, hope I haven't given a confusing description of this.

Thanks
Hasiel

First
for most users once a week is too much Defrag, if used in excess can actually hasten a failed hard drive. When you defrag you are moving large amounts of data around. This translates into heavy use of the hard drive and therefore decreasing its life. Others may disagree, but it makes sense to me and I act accordingly with my computer. To put it another way, less than 10% needing a defrag, does not affect performance, so why defrag.
May I suggest, download Auslogics defrag. It has an analysis function to show how much needs defragging. It is suggested that you wait until you reach 10%. Many at the Forum feel that Auslogics is one of the best defrag software.
Disk Defrag - Best Free Defrag Software For Your Hard Drive
I use it exclusively and am very satisfied. It is not good to use different defrags on a regular basis. A one time switch would not be a problem.
I hope that my suggestion helps you with your problem. If you want to keep on a schedule, others may come by with suggestions.