Any hex editor that can read disk sectors directly can handle this. One such is HxD for Windows.
Note, however, that checking the sectors where the file most recently lived does NOT tell you whether there is any data from the file remaining. Merely deleting at the file level does nothing at all to deal with, for instance, a file that was recently defragmented - the old sectors are now "free", but still contain that file's data.
If you really want to securely delete, wipe the entire drive, verify it, and then shred it or wrap it carefully and hit it with a hammer until little tiny glass shards are visible.
If you must do only a partial secure delete, you can try deleting that file, verifying the most recent location, and then doing a full free space delete. Piriform's CCleaner does have secure erase options, and free space erase options that at least once were reasonable.
- If you go that route, you're going to want to wipe your free space + cluster tips once, and then build a few huge files of, say, all 0's that take up most of the remaining drive space so the next free space delete is easier.
- You'll also need to do a free space + cluster tips erase after every defragging.
- And probably routinely, for that matter.
