The h5 file that I have has the exact same structure as an hdf5 file (As it is the exact same thing), but HDFView doesn’t recognize it as a valid format if it doesn’t have the .hdf5 extension. Can I somehow change it so it opens normally?
HDFView is able to open HDF5 files that have different extensions.
Does the name of the file contain non-ascii characters? HDFView will not be able to open a file with unicode characters in the name (or in the path to the file).
Can you view the file with h5dump or other HDF5 tools?