Sen2cor error: L2A_Process --help. Could not load "hdf5dll.dll"

After installing Anaconda and sen2cor-2.3.0. I performed the L"A2_Process --help" in a command prompt to check the install as per the instructions. I received what looks like a number of errors. The output is here:

Microsoft Windows [Version 10.0.14393]
© 2016 Microsoft Corporation. All rights reserved.

C:\Users\Murray>L2A_Process --help
Traceback (most recent call last):
File “C:\Python27\Scripts\”, line 9, in
load_entry_point(‘sen2cor==2.3.0’, ‘console_scripts’, ‘L2A_Process’)()
File “C:\Python27\lib\site-packages\”, line 357, in load_entry_point
return get_distribution(dist).load_entry_point(group, name)
File “C:\Python27\lib\site-packages\”, line 2394, in load_entry_point
return ep.load()
File “C:\Python27\lib\site-packages\”, line 2108, in load
entry = import(self.module_name, globals(),globals(), [‘name’])
File “C:\Python27\lib\site-packages\sen2cor-2.3.0-py2.7.egg\sen2cor\”, line 7, in
from tables import *
File “C:\Python27\lib\site-packages\”, line 65, in
‘Could not load “hdf5dll.dll”, please ensure’
ImportError: Could not load “hdf5dll.dll”, please ensure that it can be found in the system path

Any help to correct this would be appreciated.

can you go to C:\Python27\ and do a search if the file hdf5dll.dll exists?

I’d say it should be called as hdf5.dll by the script…

If you don’t find it, please check if you have hdf5dll.dll in C:\Python27\Library\bin.
Copy it and rename the copy to hdf5dll.dll. I dont know if this works but it’s worth a try.

I found hdf5.dll in C:\Python27\DLLs. I made a copy and renamed hdf5dll.dll
This didn’t work.

I opened the C:\Python27\Lib\site-packages\ file and found reference to the “hdrs5dll.dll” second last line below:

# In order to improve diagnosis of a common Windows dependency
# issue, we explicitly test that we can load the HDF5 dll before
# loading tables.utilsExtensions.
if not _load_library('hdf5dll.dll', ctypes.cdll.LoadLibrary):
    raise ImportError(
        'Could not load "hdf5dll.dll", please ensure'
        ' that it can be found in the system path')

hdf5dll.dll errors seem to occur according to this document:
Maybe I’ll try to reinstall Python27.

maybe I was wrong. hdf5dll.dll is a valid file. You can try installing the HDF5 framework again:

and maybe also the
Microsoft .NET Framework SDK

I downloaded the documents and installed it but I don’t know what it really did.

I couldn’t find a site to see about reinstalling the .net framework SKD.

I also uninstalled sen2cor, downloaded it again and installed it again after performing a windows 10 registery check (which did find and fixed a few files).
This did not work. Same errors.
What I will try to do now is install on another Windows 10 computer I have to see if the issue is specific to the one computer giving me errors.
Stay tuned and thank you!

I successfully installed sen2cor on another computer running Windows 10 so I guess it’s a computer specific problem and not something I’m doing incorrectly. I will try to resolve the issue and post the solution.

I successfully installed sen2cor on my computer I was having trouble with! I “reset” my operating system and this appeared to repair the .dll file.
I found that the digital paper and video documentation was not entirely clear and the install steps seemed to have changed slightly which caused some slight confusion but which were eventually overcome.

1 Like


I’m having the same error as you. Under C:\Python27\Lib\site-packages\tables I found hdf5.dll file but hdf5dll.dll is missing.

What do you mean by “resetting” the operating system? Did you do something differently during sen2cor installation or did you reset the BIN, SEN2COR_BIN and PYTHON_BIN in SNAP under Manage External Tools after the installation? After the resetting, did you have the hdf5dll.dll file somewhere?

Thanks for the help!

My apologies for not responding sooner. I some how stopped receiving Forum notifications.
For record keeping at least:
I performed a computer reset offered by Windows 10.
Found in: Settings>Recovery>Reset this PC>Get started

I hope this helps or that you already found a solution.