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Click the small triangle next to Eraser Schedule. Then select New Task. In the window that opens, select Run Immediately and then click Select Data.
This will open a browsing window. For "Erasure Method," choose "Pseudorandom Data (1 Pass)." Under "File" click "Browse" and find the file you want to securely delete In this example, we will delete "Secure Information" from "My Documents."
Click OK to add the file to the Data Set. When you press "OK," the file will be deleted. At this point, you will not be able to recover the file, so make sure that you have selected the correct file before pressing OK.
Secure Deletion for Macs
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