Not sure what the exact wording was, but yesterday after I washed my car the above message (or something similar) showed when I went to return it to the garage. Nothing abnormal occurred; the car started just fine and no recurrence of the message has manifested itself. I'm not going to worry about it unless it happens again, but wonder if anyone has experienced anything similar.
I could not find any such message in the owner's manual.

 

Yikes ! Read thread on LOCKED OUT!
The message probably said ( Key FOB not recognized )
That ironically is how my FOB dilemma started with washing the car.

After reading the thread, hopefully your not headed down that road.

 

If the car still started without placing the fob next to the detection pad, it may have been a momentary signal block due to some physical obstruction (like a fat butt ), and the signal was regained while you were still pushing the button. Also could be time to replace the fob battery. Interestingly, I've had the same battery in my MINI fob for over 12 years.