These are almost the same texts: Scroll Lock On vs No Scroll Lock.
Different order of words and characters – that’s it – yet such a difference this makes for Excel.
And indeed: Excel shows my Scroll Lock key was pressed and it is now “on”.
And yet, my keyboard shows no such key present.
Frustrating.
Surely I must have pressed some mysterious combination of keys to this effect.
And indeed it was so: that combination turns out to be Win +Fn +S.
Excel will tell you if that works (see the bottom left of the screen).