You're welcome. And by the way, Auslogics is far superior to the defrag that comes with Windows. And the reason Auslogics didn't make any difference is that it did not see that partition because it...

Ok, there's your answer. That is a reserved system partition. With no drive letter. It cannot be defragged. It's small, about 100MB. Just ignore it.

If you could take a screenshot of the screen where you are optimizing your disk drives and still see the 15%, that would be helpful. Follow these two tutorials on how to take a screenshot and how to...

Before changing the picture too much, it would be nice to know the hardware.

Coned1022, what kind of drive is it? A screenshot of the Defrag screen would also be helpful.

Screenshot - Take in...

What type of drive is it? Make and model....