Adjust Co-ordinate system

Hi Team,
I ran "Process > Import > Channel file > Adjust coordinate system. " And getting the following error - Can you help me resolve it ?

Make sure you select the proper file format for your channel or data file using the pulldown menu in the open file window. From the error message, Brainstorm is trying to read from 4D/Bti data recordings ; is that the file format of your data?

Thanks Sylvain! I realised I had selected the wrong format.