Did you by chance turn off anything DELL related in the Startup list in msconfig? Type in Run msconfig and find it out. Or have you uninstalled Dell software? That might be the cause as well, because these buttons depend on a software to control their action.

I have not changed any settings, just got the computer today .... and my display on/off button does not work either.

I think it's a buttom to change the display (projector)

That key works when you connect an external display. The key is a "switch to external monitor" button. Look up Display in Windows Help for info about multiple monitors.

Hi . i purchase n5110, and m facing the same problem with the PC, screen also dont turn off when wuto turn off setting is changed in power management. Hot keys on keyboard are not working for display

Hi

Install Dell QuickSet Application and your problem will be solved.

thanks buddy its woks.....................:emotion-21:

Thanks,it works...

I have installed window 10 and there is no quickset app for window 10. Please let me know what will i do so that my laptop screen off button work normally.