To obtain the device information:
Download and run the Device List Tool on the Windows endpoint where the external device is connected.
For details on how to use the tool, see Running the Device List Tool.
Check the System Information on the Mac endpoint where the external device is connected.
For details, see Getting Device Information on Mac.
Check the Device Control log details if Device Control violations have occurred.
Add: Adds the exception to the list
Add Another Device: Adds the exception to the list and lets you add another device information