A method of scanning secure data in a data store is performed in a manner that does not expose the scan data, the files being searched, or information about when matches occur between the scan data and the files. During the scan process, encrypted versions of searched files are compared to encrypted versions of match strings, and any resulting match data is encrypted before being written into a results file. In addition, to disguise when match entries are written, during the scan one or more encrypted dummy items are written into the results file.