PNPI Software Tools: Eraser 5.8

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Installing Eraser 5.8

Using Eraser 5.8

Eraser Options

IT Help Center
Last Updated: 11/3/09
Copyright © 2005 University of Delaware

Delete Files Securely using Eraser 5.8

When you remove files on your computer by emptying the Recycle Bin, you most likely think that this process "deleted" the files from your computer.

What really happens is that the directory information that allows the Windows operating system and other software to find the file is discarded. However, the information itself remains on your computer's hard drive until another program writes information onto that specific area of your computer's hard drive. Therefore, if your computer is lost or stolen, a disk recovery program may be able to find nearly all of the contents of "deleted" files, including PNPI.

If you have PNPI that you want to remove from the hard drive completely, you can use a program called "Eraser" to eradicate files which removes the directory information and the contents of a file from your computer's hard drive. A disk recovery program will not be able to find files eradicated using this program.

Installing Eraser 5.8

  1. Download the installer from and save it to your computer's desktop.

    You can also download the software from One of these URLs should work for most users:

  1. Locate the installer on your computer's desktop.
  2. Double-click the installer to begin the installation process.
  3. The installation process for the Eraser program is very similar to other programs: Follow the on-screen directions.
  4. When the installation process is almost complete, you will see a window that looks similar to the following:

complete installation window

  1. Close all open programs and click Finish. Doing so will reboot your computer.

Using Eraser 5.8

Erasing a file or the files in the Recycle Bin

Eraser adds a context menu to Windows Explorer so that when you right-click a file or folder, you have the option to Erase a file. This option is indicated by the red arrow in following graphic:

securemove window

When you choose to Erase a file or folder, you will see a prompt asking you to confirm your decision because erasing a file using the Eraser program is an irrevocable action. When you choose to Erase a file or folder, you will NOT be able to recover the file. The prompt will appear in a dialog box that looks similar to the following:

confirm window

If you have items in your computer's Recycle Bin, right-clicking the Recycle Bin will reveal the Erase Recycle Bin option. Selecting this option will securely erase everything in the Recycle Bin.

Erasing all free space

You can choose to erase all the "free space" on your computer's hard drive by running the Eraser program from your computer's Start menu.
  1. Click Start.
  2. Click All Programs.
  3. Click Eraser.
  4. Click Erase. You should see a window that looks similar to the following:

ondemand window

  1. From the File menu, click New Task (as shown in the following graphic).

new task window

  1. Select the drive on which you want to erase the free space. In the following example, the C drive is selected. Click OK.

drive to erase

  1. From the Task menu, click Run (as shown in the following graphic).


  1. When prompted to confirm your decision, click Yes.

This task may take a long time (a few minutes or a few hours). Eraser shows a progress chart as it is performing the erasure (as shown in the following graphic).

erase window

  1. After the erasure is done, click Close.

Eraser Options

Selecting the Options button in the Confirm Erasing dialog box (as shown in the following graphic) gives you more control over the method of erasure.

confirm window

By default, Eraser uses a more secure method to erase files than it does to clean up the free space on your hard drive. You can increase the security of the free-space erasure by choosing a more secure method. Be aware that doing so can increase the length of time it takes to erase the free space on your computer's hard drive.

  1. In the Confirm Erasing dialog box, click Options. You will see the Preferences: Erasing dialog box.
  2. Click the Unused Disk Space tab.

us dod window

  1. By default, option number 4 is selected (Pseudorandom Data). If you wish to increase the security of the free-space erasure, click option number 3: US DoD 3-pass method (as shown in the graphic above).
  2. Click OK.

Scheduling automatic free-space erasure

You can use the scheduling capabilities of Eraser to regularly run free-space erasures of your hard drive. However, be careful about Eraser interfering with your regular work schedule. To set up a free-space erasure schedule, follow these steps:

  1. Click Start.
  2. Click All Programs.
  3. Click Eraser.
  4. Click Erase.
  5. Click Scheduler from the left window pane.
  6. From the File menu, click New Task.
  7. On the Data tab, verify that your computer's hard drive is selected.
  8. Click the Schedule tab and select the date/time you would like your hard drive's free space erased.

time of day window

  1. Click OK.

Remember, be careful to schedule this task for a time when you won't be using the computer.