I have a laptop running Winodws xp pro. It works fine with the regular screen. But not with the external screen. The xp boot screen will show on both the laptop screen and the external screen. After that the external screen goes black, but not the laptop screen..

Please help me! It sounds like "Display Properties" set for the laptop screen (refresh rate, COLOR depth, resolution) are OUTSIDE the range external screen can handle.  While on the laptop screen set display properties to LESS demanding values.  For example:
     o  Refresh rate - 60 Hz
     o  Color depth  - 16 bits
     o  Resolution    -  800 by 600 pixels

Reboot to external screen.  If it accepts those values, you may try to adjust higher.  Do not push refresh rate beyond what the screen is designed to accept.
How do you intend to use the monitors (internal and external SCREENS)?  As a single monitor or dual monitor system?

If dual monitor, will screens be independent of each other or display the same image?Thanks dahlarbear I got it to work!!  !!!!!

p.s. I thank all that RESPONDED to this post. I was kind of a dumb problem. Thanks for the help!Where on earth did you find all those smilies ? ?