How To Overwrite Free Space Securely in Windows. As a keeper of client confidential data, lawyers have higher obligations than the average computer user. We must always exercise reasonable controls over the data we store, and restrict its access to the best of our ability. That means taking reasonable safeguards to protect that data. But, what about the stuff we delete? What about the stuff we no longer need? When we hit the delete button for a document, what happens to the data? Well, long time computer users know that the OS merely deletes the indexing data to the document, and does not delete the document itself. The bits and bytes remain on the disk, until another program writes new data over it. Low level software can easily recover that data, and all that is needed is possession of the drive. In the case of investigations by proper authorities, this can be a good thing. For us lawyers, however, it is a bad thing if we intend to protect our clients' documents. Using simple command line commands, as an Administrator on a Windows computer, the user can write over data in the open space on the drive as many times as is necessary to make it inaccessible to anyone. Check out this article to learn how. And, learn this before you pay good money for a commercial software package that promises the same result.