As you probably suspect, Windows doesn't show you everything that's on your hard drive. However, Disk Investigator does. It's a free, compact tool that searches your hard drives and displays everything that's on them, bypassing your operating system and reading the raw data, sector by sector. With it, you can examine raw directories, files, clusters, and system sectors, which is especially useful when you're reusing a disk or upgrading your OS. You can also use it to verify the effectiveness of disk-cleaning utilities and even recover deleted files and lost data, in many cases.
This simple but effective tool opened with a dialog-based interface displaying the raw contents of our C: drive in the main window, with a single cluster highlighted. You can select any cluster, click View Cluster, and call up a display of the raw file contents. To the left of the main window are options to view disks or directories, a drop-down menu displaying all disks on the system, and a panel displaying disk information for the selection. The software identified all seven logical disks on our system; clicking any called up the disk's details. There's a handy slider bar at the bottom that lets you quickly move from the front to the back of the disk, and disk search tools, too. Clicking the Directories view changed the main display to a scrolling, color-coded, gridded list view of our system's directories; clicking any entry called up a dialog with detailed information and displayed the directory in the browsable left-hand tree view. There's even a handy Hex Converter tool on the Help menu, which also accesses a fully indexed Help file that explains what the program shows about your disks.
Disk Investigator is fairly unique in its ability to display the raw data on your hard drives. Its undelete capabilities will come in handy to a wide range of users, but those with more experience, such as system administrators and programmers, will get the most of the incredible detail and raw data this fine tool uncovers.