When reading eBooks which have been divided into a Contents PDF and Chapter PDFs a Security Warning Message appears everytime you select a Chapter to read from within the Contents document.
If you select Edit / Preferences / Security (Enhanced) from the top toolbar you can add the Folder Location of the PDFs into the Privileged Locations box but this fails to stop the Security warning message box appearing. If you add the File Names of the PDFs into the Privileged Locations box it may work the first time but then fails to stop the Security warning message box appearing on subsequent times the Chapter is selected.
To Summarize both the Folder and File Options for the Privileged Locations in the Security (Enhanced) Preferences fail to work as described and make reading eBooks using PDFs almost impossible.
This is a major Security Bug and needs to be fixed as users may be tempted to switch off the Enhanced Security feature to resolve the issue rendering their computer open to attack.