Error while performing an unattended install

[Hughesmar]

So I've followed the slipstream guide here and created an unattended.mst file using the guide here and placed it in the folder that contained my slipstreamed office files. I made my autorun.inf file look like this:

[autorun]
OPEN=SETUP.EXE TRANSFORMS=Unattended.MST /qb-
ICON=SETUP.EXE,1

shell\configure=&Configure...
shell\configure\command=SETUP.EXE

shell\install=&Install...
shell\install\command=SETUP.EXE

I burned the contents of that folder to a cd. Attempted to run the CD and the installation kicks off OK. After about five minutes or so I'm presented with this message:

Any ideas why this would be popping up?