Numlock wierdness

My numeric keypad is always in “Numbers off” mode even though the Num Lock light is lit up. I am using 11.3 and have a Microsoft Natural Ergonomic keyboard 4000.

Any clues as to how to fix it?

[edit]It doesn’t appear to be doing anything[/edit]

I had a problem like that, where I couldn’t use the numeric keypad.

I had enabled assistive technology, and I had set keyboard preferences to access assistive technologies using keyboard shortcuts.

When I unchecked that button/box I got my numeric keypad back.

Thanks. That wasn’t the cause in my case but you pointed me in the right direction. In my case, I had somehow turned on mouse keys. When I turned it off again, all worked as expected.