external monitor display probl

Could anybody help me, thanks a lot?

my laptop display is fine when i display things on its own monitor. But when it displays to outside monitor. It has problem. For example, for our university website, it can't display the background frame, meaning the graphic is not that cool as its own monitor.

for our school, every laptop has a dock connecting to external monitor. I want the display to be normal since sometimes i work on the website. If my display is different, i will have trouble.

Anyone help, please?