Well I'm not sure if this would work for you but it sure worked for me. I currently use Toshiba Notebook of the F20 series.
I had the same problem and I managed to fix it successfully. Here's what I've done:
I uninstalled the Toshiba Hotkey Utility and Toshiba Utilities.
After rebooting the computer I clicked on Toshiba Assist icon on the desktop.
Next I clicked on the Protect and Fix tab and then Preinstalled Drivers Depository.
A screen appears displaying tools and utilties. Just click on it and you should have a list of the preinstalled files on the left.
I suggest that you click on the Common Modules first and install that before installing other Toshiba components.
Afterwards install Toshiba Utilties and Toshiba Hotkey for Display Devices.
This should hopefully help.
My apologies if this doesn't work out.
Edited by GCMM, 14 November 2007 - 06:35 PM.