Toshiba Satellite a45-s121 laptop VGA port with LCD projector ?

[bamx2]

I am trying to use this machine with an LCD projector . When it intitally boots, I get the XP logo and start up bar then when it goes to the desktop the LCD looses the signal from the VGA port . What is going on and how do I change the setting on the laptop to make it work with the projector . - Thanks