When you download a file to your computer through the browser and Internet connection, your computer saves files in a temporary folder. From here, an administrator or third party can read the files you've saved to the hard drive. This leads to snooping from third parties, and it can also lead to identity theft from unscrupulous hackers. The deletion process for these files can be found in the browser's settings. Firefox and Internet Explorer have options through the "Tools" menu to delete download history.
Click the "Tools" option from the main menu bar. From that menu, select "Internet Options" from the list of options. This opens a dialog box where you edit all browser settings.
Click the "General" tab in the dialog box. Within this tab, check the box labeled "Delete browsing history on exit." Click the "Delete" button to instantly delete the information.
Check all the boxes in the confirmation screen that pops up. Click the "Delete" button. This deletes all the history on your machine, including the download history.
Click the "Tools" menu item on the main menu of the Firefox screen. Select "Downloads" from the list of options.
Click the "Clear List" button that is shown on the download window dialog. This dialog box lists all the downloaded files in Firefox. When you click this button, the history is removed.
Close the dialog box and resume use of Firefox. Note that any downloads after this point are logged, so repeat these steps if you download more data using the browser.
Once you delete the browser history, you must delete any copies of files or application installations from the programs you've downloaded.