Block opening of Open XML file types

This policy setting controls whether users can open Office Open XML files in the specified applications. Office Open XML files usually have the following extensions:

- Excel: .xlsx, .xlsm, .xltx, .xltm, .xlam

- PowerPoint: .pptx, .pptm, .potx, .potm, .ppsx, .ppsm, .ppam, .thmx, .xml

- Word: .docx, .docm, .dotx, .dotm, .xml

If you enable this policy setting, users cannot open Open XML files in the specified applications. This policy setting can be used to guard against theoretical future zero-day attacks that target specific file types.

If you disable or do not configure this policy setting, Open XML file formats are not blocked.

Supported on: At least Windows Vista
Registry PathSoftware\Policies\Microsoft\Office\12.0\Excel\Security\FileOpenBlock
Value NameOpenXmlFiles
Enabled Value1
Disabled Value0


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