While Traktor’s beat gridding system is quite flexible, it has some specific behavior that means not every grid coming from another app will be supported.
The main reason for this error message is usually multiple BPM values are being found in the grid. When you analyze a track using ‘dynamic’ modes in another app or when you’ve beat gridded a track which tempo’s changes throughout the track, you may encounter this.
Traktor only supports one BPM value for the entire track. You can add multiple grid markers to correct the grid on tracks that have varying tempo but in Traktor those grid markers all have the same unique BPM value.