KB001674: What does Error Message "No MS Data" Indicate When Loading a Data File? - MS ChemStation 

Mass Spectral data actually consists of a folder / directory with a few files underneath rather than a single file. The actual raw MS data is contained in the data.ms file in the data directory. A data directory is created when you start a measurement. If the data acquisition is cancelled (aborted), the data.ms file will not be created but the data directory will remain. The ”No MS data” error occurs in this situation. The data cannot be loaded because no data was collected.