Determining what is causing file incompatibility with v1.8

I have an HDF5 file (NetCDF-4) which is not readable by client software using HDF5-1.8.X libraries. The NetCDF library which created this file does have the call to create V18 compatible files:

netcdf-c-4.6.3/libhdf5/hdf5create.c: if (H5Pset_libver_bounds(fapl_id, H5F_LIBVER_EARLIEST, H5F_LIBVER_V18) < 0)

And that piece of code is being called, but the files are not readable and give the following error from h5check:

VALIDATING /Users/gds/file.e according to library version 1.8.0

Error

Superblock:Unable to find super block signature at addr 0

End of Error messages

Error

Errors found when checking superblock. Validation stopped.

Superblock v.0/1:Undefined object header address in root group symbol table entry at addr 24

Superblock v.0/1:Invalid End of File Address at addr 24

Superblock v.0/1:Invalid base address at addr 24

Superblock v.0/1:Invalid file consistency flags. at addr 20

Superblock v.0/1:Invalid value for file consistency flags. at addr 20

Superblock v.0/1:Invalid value for Group Internal Node K at addr 18

Superblock v.0/1:Invalid value for Group Leaf Node K at addr 16

Superblock v.0/1:Invalid Size of Lengths at addr 14

Superblock v.0/1:Invalid Size of Offsets at addr 13

End of Error messages

Non-compliance errors found

Based on this output (or using some other tool), is it possible to determine what HDF5 function call is causing the file to no longer be compatible with V18 clients? This is using HDF5-1.10.5

Thanks,

…Greg

Never mind… NetCDF was creating a CDF5 (PNetCDF) and not NetCDF-4 format file.

…Greg

Uh… Thank you for clarification!