I was finding DF to work very well using Defrag and Quick Defrag. Then I discovered Free Space Deftag so used it. Then my troubles began. The fragments and fragmented space grew dramatically, up to 50% fragmentation and 50 GB fragmented. The amount of the HD used increasd by 20-30GB. I resolved it by running a Free Space Defrag (framents allowed). Finally it is back to normal after a lot of work and time. I did a restore of systems files retaining current data which did not help or change things at all except losing some updates and programs that I installed. I have Win 7 and all of the setting of DF were in the default state. I have the free version. This is definitely a bug or you could say it could be a problem with my computer. Right now I plan to run DF but NEVER defrag free space! Question, if I uncheck the disable Windows defragger does that enable it?