Remove Properties and Personal Information: A Misleading Feature!



The Remove Properties and Personal Information feature has been introduced in Windows Vista® by Microsoft® to allows users to remove metadata from several file formats, either from one file at a time or from a group of files. Removing metadata from files before sharing them with others is important for preventing sensitive personal information leakage. However, this feature is unsuitable for the task since it supports a small number of file formats, it can remove a small number of metadata elements, and above all, it provides a dangerous false sense of privacy protection due to its highly misleading user interface.

Screenshot of the Remove Properties and Personal Information link

To access this feature, select one or more files in Windows Explorer, right-click and select Properties from the context menu. In the Properties window, select the Details tab, and then click on the "Remove Properties and Personal Information" link at the buttom.

The Small Problem: A Very Limited Support of File Formats and Metadata Elements

The Remove Properties and Personal Information feature has a built-in support for the removal of only a small number properties from only four supported file formats: JPEG, PNG, MP3, and MP4.

It's possible for software developers to extend the supported file formats and metadata formats of the Remove Properties and Personal Information feature. Notably, if Microsoft Office® is installed on the computer, the Remove Properties and Personal Information feature can also remove some properties from Microsoft® Word, Excel®, and PowerPoint® files.

Even when removing all possible properties that this feature supports from supported file formats, a wealth of potentially harmful hidden data & metadata are being left in the files.

The following table summarizes the built-in support for the removal of properties by the Remove Properties and Personal Information feature in Windows 10, and the unsupported hidden data & metadata:

Supported File Formats Supported Metadata Unsupported Hidden Data & Metadata
JPEG Image 28 properties, mostly of Exif data and a few of XMP and IPTC data Most Exif data, including thumbnail and camera & lenses serial numbers; Most XMP & IPTC data; JPEG Comment; Other types of hidden data
PNG Image Date taken Most native properties; XMP
MP3 Audio 21 ID3v1 tag and ID3v2 tag properties Few ID3v2 properties; XMP; APE
MP4 File 25 properties XMP

The following table summarizes the additional support for the removal of properties by the Remove Properties and Personal Information feature when Microsoft Office® is installed on the computer, and the unsupported hidden data & metadata:

Supported File Formats Supported Metadata Unsupported Hidden Data & Metadata
Microsoft® Word Document

Microsoft Excel® Workbook

Microsoft PowerPoint® Presentation
15 Document Properties Six Document Properties, including total editing time, template, created, modified, and last printed dates. Also, Custom Properties; Comments; Comment Authors; (Common to all)

Hidden Text; (Word only)

Tracked Changes; Custom XML; Printer Settings; (Word & Excel only)

Hidden Worksheets; Hidden Rows and Columns; (Excel only)

Slide Notes; Hidden Slides; Off-Slide Content; (PowerPoint only)

The Big Problem: A Highly Misleading User Interface

Screenshot of Remove Properties and Personal Information

However, there is an even bigger problem than the very limited support of file formats and metadata elements - its highly misleading user interface! After clicking on the "Remove Properties and Personal Information" link, the user is presented with the "Remove Properties" window. In it, the user have two options to choose from: "Create a copy with all possible properties removed" and "Remove the following properties from this file".

The user might easily believe that the file contains only the properties shown in the window, when in fact it may, and often does, contain a whole lot more properties and other types of hidden data.

Also, the user might easily believe that selecting "Create a copy with all possible properties removed" will create a copy with all possible properties THAT FILE CAN HOLD removed, when in fact it will create a copy with all possible properties that THIS FEATURE SUPPORTS THEIR REMOVAL removed. The properties that will be removed are only the ones that have check boxes next to them, when selecting the option "Remove the following properties from this file". If the file format is not supported by this feature, it will create a completely identical copy of the original file, without warning the user that nothing in fact was removed from it. This feature will even allow the user to remove metadata from file formats that cannot hold any metadata. (e.g. Plain Text .txt files )

In addition, if the user attempts to remove all properties from multiple files of different types at once, only the properties that are common to all selected files will be removed. This happens even if the user chooses to create a copy with all possible properties removed. For example, if the user removes properties from a Word file and a JPEG file at once, only the common six properties will be removed from the selected files. (where this tool supports 28 JPEG properties and 15 Word properties)

Other Shortcomings

  • It cannot remove properties from files in different folders at once, and the user cannot select folders to remove metadata from the files inside. The user must select files only from one folder at a time.
  • It cannot remove properties from files compressed in ZIP files
  • If the user wishes to selectively remove some properties from a file, the user cannot save it as a new file while keeping the original file with all the properties intact
  • It cannot save copies of the files with their properties removed to a different folder

Conclusion

The Remove Properties and Personal Information feature is not a reliable tool for removing potentially harmful hidden data & metadata from files. To properly remove hidden data & metadata from files, one must use a dedicated tool for the file types one wishes to clean, with a broad spectrum of supported metadata types.

For Microsoft Office® files, for example, the integral Document Inspector tool that is included in Microsoft Office® does and excellent job. However, this tool has no batch hidden data removal capability. There are, however, third-party tools for removing hidden data & metadata from multiple files at once, such as BatchPurifier.

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