Recently noticed my C: drive had almost maxed out (47 GB free of 457 GB). Knowing this wasn't right I did a quick total of all the files which came out at about 250 GB. I then went back and carefully checked each folder and file and still came up with 250GB. Then I downloaded an analytical software WinDrStat and it confirmed my total...until I selected Show Unknown files and sure enough there are about 154 GB of files residing somewhere on my HD. In fact the amount corresponds very closely to my Users folder which is 158 GB. So where are the "hidden" files lurking and how do I access them and delete them?