FABL1021E LIBRARY MISSING: `ddname` DD

Explanation
 Data set ddname could not be
opened during initialization. The ddname is the
 DD name of the DBDLIB/PSBLIB/ACBLIB data set.

System action
  IMS Library
Integrity Utilities Interface
 returns return code 16 to the caller.

User response
 Determine whether the required libraries  are
specified in DD statements. Correct the problem, and rerun the program. 