When running Batch & Print Pro as a NT Service there are certain restrictions that don't allow some of our addons to work without some modifications to the BPPNTService.ini configuration.

Addon's that work with NT Service default install are: IMG Addon, TIFF Addon, DOC Addon, Excel Addon, PDF Addon, PowerPoint Addon, MSG Addon, EML Addon

Addon's that don't work without changes to the BPPNTService.ini are: PDF Addon Plus, eDrawings Addon, Solid Edge Addon, DWF Addon, HTML Addon

The reason why is because these addons above need to control the 3rd party application interface (click buttons etc), An NT Service by default runs without an interface, so the Addon can't interact as there's nothing on screen.
To get around this it's still possible to run as an NT Service but you will need to change the file: C:\Program Files\Traction Software\Batch & Print Pro\BPPNTService.ini

Change line: UserInterface = No   to  UserInterface = Yes             (Case sensitive)