I am using suse 10.1 on my laptop.When I run video clips connected with projector by VGA cable ,it shows blue screen on externel screen.But internel screen shows normal. How can I solve this problem?

What video player are you using? If it's not mplayer, try mplayer and all the different output options (Xv, gl, x11 etc.). This should help you narrow down the problem.

Your description of your problem is not clear: Can you see the other (not video clip) parts of your desktop? If not then remember that laptops often need to have an external video output "enabled". Usually by something like <Fn>-<F5/6> - Check your documentation for the laptop.

HTH

i have had this problem with laptops several times...
no matter what the os

it is normally caused by the vidio being rendered by the graphics card for the LCD screen only not by the processor/main graphics card rendering
this speeds up play (especially in windoze)
but means that you cant see it on a projector,
unfortunatly i dont know where the settings for this are in linux... (in windoze they are with the setup software that is laptop specific) if you have a dual boot then try from the windoze side...

anyone know where thise settings are in linux?
(they might be in the bois aswell, you could try there)