Over 100GB Gone After Doing A Clean Install

Recently my computer has been running a bit slow, so I decided to erase everything in order to get some memory back, to see if it will help. As I wasn't exactly sure how to delete everything on my hard drive, I attempted to just reinstall Win7 again, but with a clean install. I'm pretty sure I screwed something up here... I think I might have 2 copies of Win7 on my computer now, because after I did the clean install, I have over 100GB less disk space free now. Any help would be greatly appreciated, thank you.


(Sorry if this is in the wrong forum)

It wasn't exactly over 100GB of memory lost, but I didn't have much on my computer, only about 10GB used and now I have about 80GB used. My disk space free used to be in the mid 90s, now it's in the 60s. This is my Disk Management...

If you look at your Disk Mangement listings columns, it shows you're only using 10gb on C.

I'm not sure what you mean... If I'm only using 10GB on C then why do I only have 68% of my disk space on C free?

go to your hard drive C:. do you have a folder called windows.old? if you do, its ur old windows setup. go to disk cleanup to remove it

I checked and it appears that I do have a windows.old folder. Is there any special way to delete it, or just click and delete?

Btw, thank you for all your help, this has been bugging me. :)