After installing Symantec Endpoint Protection with Network Threat Protection, Network Threat Protection does not appear in the Symantec Endpoint Protection interface.
After the initial install and system reboot, Network Threat Protection is not visible in the client interface. The Client Management - System Log contains the entry "Failed to install teefer driver" shortly after the reboot and no related errors are found in the MSI log.
The C:\Windows\temp\teeferinstall.log will show the following error:
ERROR: Call to installNetComponent() failed: 0x800f0203
The Network Threat Protection driver normally loads after a reboot of the computer as a device driver. If the path to the location of the .inf file is not in the device path, the driver installation will fail.
Check the registry key "HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\DevicePath" the value should include %systemroot%\inf, if the entry is missing or blank, the data value should be added. A reboot is required for the change to take effect.