Just found that Windows 10 (maybe other versions) by default has Hard Drive Optimization set to on.  This basically defrags all your hard drives automatically.  I just checked (control panel>security&maintenance>expand maintenance>change maintenance setting) My system defaulted to 2am.    I rarely have my computer on at this time, so I'm guessing that it runs the next time I start up my computer, which is usually when I'm working on Sonar.  Microsoft say's that the optimization runs when the system is not in use.   Not sure what this means.  I'd hate for drive optimization to be going while I'm trying to work in Sonar.  
 
My question......I only use this computer for my DAW, It's rarely on at other times.  Should I disable Automatic Hard Drive Optimization, and Optimize manually when I'm not working?  I like the idea of keeping my drives optimized, I just don't want the system optimizing while I'm trying to work.

I would turn it off, over zealous defraging/optimizing as they call it now may not be in the best interests of your Hard Drives from what I have read. I do it manually every now and then, never came across a time when I actually needed to, ie sluggish PC or any other that was cured by a defrag. Maybe if I am going to install a large program or multi gig expansion or something I will give that drive a quick blast before install. I do it once a month or probably less.

The schedule settings are pretty crappy - you can't configure some drives to be on an automatic schedule, and others manual? I do not wish to reduce my SSD's lifespan through regular defrags that it doesn't need, but I would quite like to defrag my audio drives every now and then. I guess I'll just disable it and reinstall Auslogics Disc Defrag.