Python Script node problem: Library/DLL not found // Unsatisfactory solution

[schuppius]

Hello everyone,
I was hoping you can help me with my problem. I kind of solved it, but my guess is that a better solution is needed, latest for the next upgrade of the software.

I use KNIME 5.1.0, and I could not get the bundled Python environment to work so that I can use the Python Script node.

When I executed the node with a simple

import knime.scripting.io as knio
knio.output_tables[0] = knio.input_tables[0]

I got the following error messages:

Failed to initialize LZ4 libraries. The Columnar Table Backend won’t work properly.
Execute failed: no jnijavacpp in java.library.path: C:\Program Files\KNIME;C:\Windows\Sun\Java\bin;C:\Windows\system32;C:\Windows;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0;C:\Windows\System32\OpenSSH;C:\Program Files (x86)\Novell\ZENworks\bin;C:\Program Files\Graphviz\bin;C:\Users\jschuppi\AppData\Local\Microsoft\WindowsApps;;.
Error loading model settings
Execute failed: Could not initialize class org.knime.python3.scripting.Python3KernelBackend

In the detailed error log, I got, in addition to these lines, the following:

Caused by: java.lang.UnsatisfiedLinkError: C:\Users\jschuppi.javacpp\cache\windows-x86_64\jnijavacpp.dll: Dieses Programm wurde durch eine Gruppenrichtlinie geblockt. Wenden Sie sich an den Systemadministrator, um weitere Informationen zu erhalten

I tried the suggestion here
Problem with Python Script - KNIME Analytics Platform - KNIME Community Forum
to reinstall the Columnar Backend Extension and the Conda Extension, without any change.

I also read this
KNIME Python Integration - KNIME Extensions - KNIME Community Forum
and this
Can’t run Python Script - KNIME Analytics Platform - KNIME Community Forum

My IT department informed me that we have a software restriction policy in place, which is why all files under C:\Users\jschuppi.javacpp\cache\windows-x86_64\ are blocked. This policy will not be changed for me.

Then I copied the file jnijavacpp.dll from the path in the error log into C:\Program Files\KNIME (the first path in the list of paths KNIME uses to search for these .dll files). After a restart, the error message was gone, replaced one identical for the .dll file jnilz4.dll. I also copied that file over to the new path. After another restart, the Python Script node executed without error.

Now I fear that once I make the next program upgrade, I will need to go through the whole process again. Can you advise me if there are any adjustments to my KNIME setup I can make so that this manual solution is a bit more future-proof?

Thanks,
Jan

[bwilhelm]

Hi Jan,
Currently, there is no better way to solve this issue than the setup you have described. We are aware of this problem and a proper solution would require involved changes (and possibly new points of failure). Given that there is a workaround we have not implemented this yet.
You are right, the need for a workaround is not nice and it has to be updated with KNIME AP updates.
I have noted (in our internal ticket) that you ran into this issue to increase the priority for implementing the proper solution. I will let you know of updates but I cannot promise any time frame.

[schuppius]

Thank you for your feedback! I just wanted to be sure there was no better solution for me to implement for the colleagues here in the company.
Best regards,
Jan

[Daniel_Weikert]

Did you install KNIME? Maybe the zip version could work.
br

[schuppius]

No, I did not reinstall. But if we have to redo the workaround with the 5.2, then I will test this as well!