Block opening of Html and Xmlss file types

This policy setting controls whether users can open HTML and XML Spreadsheet 2003 (XMLSS) files in Excel 2007. These files usually have the following extensions: .mht, .mhtml, .htm, .html, .xml, .xmlss.

If you enable this policy setting, users will not be able to open HTML or XMLSS files in Excel 2007.

If you disable or do not configure this policy setting, Excel 2007 allows users to open HTML and XMLSS files.

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

excel12.admx

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Administrative Templates (Users)