Could not read DENSA_J from MET_CRO_3D

Dear Sir,
I have occur a error when I run cctm.csh.The error is as follow:

    GC loaded into CGRID
     netCDF error number  -40
     
     >>--->> WARNING in subroutine RDTFLAG
     Error reading netCDF time step flag for MET_CRO_3D
     M3WARN:  DTBUF 20:00:00  April 9, 2017 (2017099:200000)
     
     >>--->> WARNING in subroutine XTRACT3
     Time step not available for file:  MET_CRO_3D
     M3WARN:  DTBUF 20:00:00  April 9, 2017 (2017099:200000)


     *** ERROR ABORT in subroutine LOAD_CGRID on PE 005      
     Could not read DENSA_J from MET_CRO_3D
 PM3EXIT:  DTBUF 20:00:00  April 9, 2017 
     Date and time 20:00:00  April 9, 2017  (2017099:200000)

Thanks a lot!

Either (a) this is a bad MET_CRO_3D file (where did it come from?) or (b) it is for a time period that doesn’t contain the date&time 2017099:200000 (what does the log-message from opening this file say?), or (c) the variable DENSA_J isn’t in the file (which is another version of the “bad file” problem.