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When files are deleted using the common "delete" operation, information is only removed from files so they can't be found by the operating system. File recovery software can be used to recover this information by taking advantage of shortcomings in the standard delete operation. A program capable of overwriting the file data with random binary must be used in order to remove files permanently from your system. This process is often called shredding. 

What should be shredded?

Any information Files that you need to be completely deleted beyond recovery should be shredded. Before shredding a file, please ensure that you are not violating any State Records Laws or Sunshine Laws. Any information that needs to be maintained for Public Record should NOT be shredded (e.g, a student's proof of residency, student records, payment receipts, etc.). However, any files that may contain confidential information that is not public record should be shredded if it is no longer needed (e.g., an Excel Document used to move Social Security Numbers from one location to another that will not be used again).

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