On my newly self built computer I have looked at the properties of my system disk. It's showing: - used space 46.9 GB - free space 884 GB - Capacity 931 GB However when I run a space analyser, called WinDirStat, it shows me that the folders and files on the disk total only 16.0 GB. Why such a huge difference? Just curiosity, really. I'm not short of space. It's not a big problem ... I hope.