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About Adobe Protected View
Protected View in Adobe Reader XI or later opens potentially unsafe PDF files in a very restricted manner, inside a confined environment. To avoid being prompted to disable Protected View every time a PDF is viewed and to enable Creo View functionality, you must either turn off Protected View or add a Privileged Location for PDF files or folder paths in the Adobe Reader Security Preferences.
To open a PDF from a PVZ file, for example, you must add the client machine’s temporary folder, where the PVZ file contents are extracted, as a Privileged Location.
To open multiple PDF files from a folder location, you can add this as a Privileged Location folder path.
For more information, refer to the Adobe Reader Protected View Help.