I know that there are some PerfectDisk users out there, wonder if one of you could answer the following questions as I am currently trialling this program and trying to get a feel for it. In Task Manager PDEngine.exe and/or PDSched.exe are always running. Normally when I look PDEngine.exe is always running in the background but at this moment only PDSched.exe is running. Haven't worked out why yet.... anybody know what they both do?? Also, as I do not want to schedule anything (I would much prefer to manually run a defrag once a week or so) is there any way I can stop these two exe's running in the background all the time, or am I stuck with them?