As I wrote in an earlier post, the ambient light button on HP EliteBooks is per default mapped to switch off the touch pad. Since it’s placed right next to the function keys that increase or decrease the screen brightness, it happens quite often that the key is hit by accident.
If you’re running KDE, hitting Fn+F11 not only switches off the touch pad. You can’t even re-enable it with the System Settings manager, since System Settings -> Input Devices -> Touchpad manipulates
~/.kde/share/config/kcmtouchpadrc but the touch pad is disabled in
To re-enable the touch pad, open
~/.kde/share/config/ktouchpadenablerrc with an editor and change it to