Whenever you delete a file by emptying the Trash, it hasn't actually left your hard drive until you write over the space that the file occupied.
There are two ways to write over this 'free space'. The first is to select Secure Empty Trash instead of Empty Trash from the Finder menu. If you have previously emptied your Trash using the less secure Empty Trash command and want to scrub this space clean, go to Utilities > Disc Utility and select Erase Free Space from the Erase tab.
This is all straightforward and easy. But what can you do if you want to recover deleted files that haven't been securely deleted but also don't show up on Finder searches? There are few ways to recover them, but Smith Micro has one solution.
MediaRECOVER is a basic search engine that retrieves insecurely deleted files. You can search by file type or date of creation, and the results are displayed in the window to the left of the application. You select the file you are looking for and click Save to relocate the file to a new location. You get one chance to set the target location for all saves during the setting-up process.
We have some reservations, though. The search process is slow and not helped by the lack of refinement in the search options. There is no option to search for a file by its name, only by type or date. And when you have retrieved that lost file, why aren't there more options for where you can save that file to? After all, different files belong in different places.
Despite this, MediaRECOVER works; it only needs to find one critical file to justify the price.