Re: I have problem in adjusting Hp 1000-1420 Tu brightness and contrast

Hi sonysanam, welcome to the HP Forums. If you have Windows 8 then it could be that Adaptive brightness is on, and not letting you adjust the brightness. If that is the case, refer to this document for instructions on disabling it:  Adaptive Brightness - Turn On or Off in Windows 8

If you are running Windows 7 or Vista, refer to this document for help: Resolving Problems with the Brightness of the Display

Let me know if either of these helped.