step0-voxel Error message

[XL258]

Hi Dr. Lett,

I'm stuck in the first step,
tfce_mediation step0-voxel -i all_FA_skeletonised.nii.gz mean_FA_skeleton_mask.nii.gz
I'm using Python 2.7 and MAC system.

the error message is:

zcat: can't stat: all_FA_skeletonised.nii.gz (all_FA_skeletonised.nii.gz.Z): No such file or directory
Traceback (most recent call last):
File "/Library/Frameworks/Python.framework/Versions/2.7/bin/tfce_mediation", line 137, in
args.func(args)
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/tfce_mediation/tmanalysis/STEP_0_load_volumes.py", line 75, in run
nonzero_data = import_voxel_neuroimage(opts.input[0], mask_index)
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/tfce_mediation/pyfunc.py", line 1228, in import_voxel_neuroimage
image = nib.load(tempname)
File "/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/nibabel/loadsave.py", line 44, in load
raise ImageFileError("Empty file: '%s'" % filename)
nibabel.filebasedimages.ImageFileError: Empty file: 'de82cdbbe6734cfebf8fac7596066750.nii'

I would appreciate your help!

Best,