I met such an error when running a program of MM5.
(OS: Fedora 8)
In REGRID part, I produced plotfmt,
** pregrid version number: 0.28 **
PGFIO-F-211/OPEN/unit=13/invalid file name.
File name =
In source file plotfmt.f, at line number 42
I actually have the file ON84:1993-03-14_00, and it is not an empty file.
What is the possible problem?