I want to launch a Power Point presentation on startup - in slide show mode (I don't want to simply open the file).
This is to run on a kiosk.
From Microsoft's list of command line switches, you can use the/S
switch to start a presentation:
C:\path\to\POWERPNT.exe" /S "Presentation.pptx"
To get the slideshow to start on boot-up create a shortcut to the path given above and put it in the Startup folder in the Start menu.
you can also rename the file to pps or ppsx. this should make the presentation go immediately in presentation mode.