My cousin's computer is a Dell Inspiron i5559 Signature Edition. It came with no software except Windows. The problem is, even though I installed Dell Quickset on it we can't adjust the keyboard backlight timeout. In the Quickset program directory it has BacklitKB.exe. On mine I can use that to adjust the time out to different lengths of time. On his it gives an error message that says the backlight keyboard can't be found. I was wondering if maybe there's another program that it's dependent on. I'd hate to reinstall Windows again because we just did it to fix the issue that it had with Cortana not working. The only timeout length he can use is one minute. I keep mine set for five minutes. I have a Dell Inspiron 15 7559. We do seem to have the same keyboard.