proc contents data=libref._all_; run;  The above works for me, and the result window shows details of all the data sets in the library. However  if I use libref._all_nods I'm getting an error stating that   librf._all_nods.data does not exist.    Well we need to give a small space after _all_  since nods is an option for the proc statement. So   proc contents data=libref._all_ nods; run;   works just fine.       ... View more