As the name suggests, this The Encrypt Application Files action forces applications to use Microsoft encryption when saving a file. 
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Types of Encrypt Application Files
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From the Arellia Security Manager console, go to the Policies tab.
Navigate to Policies / Arellia Solutions / Application Control / Actions.
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Actions
Encrypt Common Application Documents - This action can be used to automatically encrypt common application documents using Windows EFS.
Encrypt Microsoft Office Documents - This action can be used to automatically encrypt Microsoft Office documents using Windows EFS.