1. Start CCleaner from your CCleaner shortcut on the desktop.
2. Tab to the , Tool button, & press the spacebar.
3. Tab to the, Drive Wiper button, & press the spacebar. Note: When pressing the spacebar on the Tool & Drive Wiper buttons, nothing appears to happen but actually there is, you just need to tab to the options.
4. Tab 1 time to the , Wipe combobox, & make sure the, Free Space Only, option is highlighted. Cautionary Note: The other option is, Entire Drive, & this will wipe all data from the drive! Do not choose this option!
5. Tab 1 time to the, Security combobox, & here you arrow up / down to select how many passes you want CCleaner to make over the free space of the drive. Your choices are:
Simple Overwrite, 1 pass.
Advanced Overwrite, 3 passes.
Complex Overwrite, 7 passes.
Very Complex Overwrite, 35 passes.
The Advanced Overwrite, 3 passes, should be a sufficient selection.
6. Tab 1 time to your list of drives, arrow up / down using the spacebar to check the drives you want to wipe the free space of.
7. Tab to the, Wipe button, & press the spacebar to start the process. Note: This can take several hours depending on how much free space needs to be wiped & how many drives are selected.