My C drive was getting full without installation so I tried defragmentation on Windows 8. My disk was fragmented about 30% and after completing defragmentation around 5Gb of space was freed but still it kept showing that disk is 10% fragmented and after trying 2-3 times nothing changed. So I used Defraggler and instead of defragging the space, it reduced free space to 1Gb. I tried boot time defragmentation but didn't get any help. What should I do?