Block saving Xml file types

This policy will prevent saving of Excel documents that have file types such as *.xml.

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

excel12.admx

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Administrative Templates (Users)