On most laptops one can enable/disable a screen by pressing on one of
the F keys together with the FN key at the bottom. I don't know which F
key is the correct one for the Toshiba but the IBM laptops use F7. The
idea is to be able to interact with a projector enabling or disabling
the projector, computer screen or using them both. There should be a
"screen" drawing on the F key meant to be pressed with the FN key.

On my HP laptop it looks like it is F4. If that does not work, I would try each
FN key. You may have to press it more than once. I've seen some that are a 3 way
switch (PC, monitor or both).

You may have to press multiple keys at the same time. I have a separate key that
has a "FN" on it to be used with the special function keys.

Which version did you run???????????????????

I tried to switch monitors using the <Fn><F6> key combo and turn off the
machine. This process failed, and the laptops display reverted to
default (on). It sounds like you tried Ubuntu from CD rather than
install, so doubt your experiment with Linux caused any problems. It is
highly unlikely that Ubuntu caused any of this kind of problem anyhow.
I have installed Ubuntu on many Toshiba computers, my own computer
included, without a hitch. Make sure the CD is out of the drive and try
starting the machine again. This time look to make sure the Toshiba
splash screen displays, if not I would guess a hardware problem. You
might also try starting the machine with CD in as it would come up using
the CD if your boot order was set for CD first, this removes question
about any writing that was done to the hard drive.

Let us know what is happening with your machine.

Look in your manual. Most laptops have a key combination, such as Fn F4, to
change the video output, for example rotating among: built-in screen, external
VGA port, both.

I can testify that the Toshiba L505 is useless with the function key. Even
selecting a toshiba laptop keyboard layout, I have not been able to get it
to recognize that the function key exists... even when trying to map custom
scripts to a Fn-F# hotkey.

Yep, I was so desperate I actually checked out the manual!

I tried Fn with f5 as suggested. Alas no luck.

Just a quick update.

Problem isn't solved yet - I'm waiting for tomorrow when I have time to talk
with Toshiba support.

A couple of things;
First thanks for all the quick replies and suggestions.

I checked the manual and tried the function key with f5 as per instructions but
that didn't work. Someone mentioned that the function key on the Toshiba
Satellite was useless. Seems to be so in Windows 7.

Someone else mentioned that since I tried Ubuntu from a CD, the problem likely
wasn't due to Ubuntu, which I tend to agree with but of course I don't know.

At this point it's looking like this is a Toshiba problem, not Ubuntu.