Making File Attachments Default to Private

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 Does anyone know of a way to set the default property on file attachments to Private? So when an agent adds an attachment to the incident, it is automatically set to private rather than the agent having to open the Properties dialog box and select Private.

We have files we need to add to the incident record that cannot be viewed by the end-user, but must be stored with the incident. I am worried agents will forget to set the property to private. Anyone have a suggestion?