Windows Vista my screen is too bright

hey, please help me.

this morning, i noticed that my toshiba laptop screen is some kind like too white. when start up, it's still normal, but after a few seconds it suddenly turned bright white. i think it has a relation with the contrast, but i don't know where to adjust it.
oh, and although i had adjusted the brightness using Fn-F6, the screen was still too white.

please help me. thank you.

 

Try booting into Safe Mode and see if it happens there.

 

no, it didn't happen in safe mode.

what should I do next??

 

I'm sorry. the first two posts seemed failed coz i used quick reply.. it stucked after i sent it.

okay, i'll try to reinstall it. thank you so much !!