Netgen DLL problem on fresh Windows 11 VM

[stenio]

Hello,

I’ve just run a fresh Windows 11 VM, installed python 3.12.4 from Microsoft Store,
installed netgen with pip install --upgrade ngsolve and added
C:\Users\User\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.12_qbz5n2kfra8p0\LocalCache\local-packages\Python312\Scripts
to the PATH environment variable, but netgen cannot start because of the following error:

C:\Users\User>netgen
Traceback (most recent call last):
  File "<frozen runpy>", line 198, in _run_module_as_main
  File "<frozen runpy>", line 88, in _run_code
  File "C:\Users\User\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.12_qbz5n2kfra8p0\LocalCache\local-packages\Python312\Scripts\netgen.exe\__main__.py", line 4, in <module>
  File "C:\Users\User\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.12_qbz5n2kfra8p0\LocalCache\local-packages\Python312\site-packages\netgen\__init__.py", line 98, in <module>
    from pyngcore import Timer
  File "C:\Users\User\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.12_qbz5n2kfra8p0\LocalCache\local-packages\Python312\site-packages\pyngcore\__init__.py", line 1, in <module>
    from .pyngcore import *
ImportError: DLL load failed while importing pyngcore: A dynamic link library (DLL) initialization routine failed.

Is there something I am missing?

Thanks,
Stenio

[stenio]

Hi,

Do you have any news about this issue? Something is definitively not working as expected if the software cannot work on a fresh virtual machine, don’t you agree?

[christopher]

This is not a real fix but as far as I know the python from the microsoft store has some weird installation behaviour… Does it work if python is installed from the python website?

[stenio]

I’ve just tried with a new VM:

1. installed python 3.12.4 from www.python.org

2. from a non administrative prompt
   pip install --upgrade ngsolve

3. and then
   netgen

Unfortunatelly I got the same error.

[stenio]

Does it work if python is installed from the python website?

No, it doesn’t. Please, see my previous post.

Thanks

[stenio]

I tried also with python 3.13 and 3.11, but I got the same error.
Seems to me that there is a problem on the package pyngcore.
This is the free VM that I used: Oracle Virtual Box.

[christopher]

Ah I think I could just reproduce the problem. Can you try installing vcruntime?

Latest supported Visual C++ Redistributable downloads

[stenio]

Hi Christopher, sorry for the delay. The virtual machine comes with the runtime already installed:

Thanks,
Stenio

[christopher]

can you load the pyngcore library into this dependency walker to see which libs it is missing?

https://lucasg.github.io/Dependencies/

[stenio]

Sure. Here it is:

[christopher]

python should be fine, this should be there at runtime. Can you find where ngcore.dll was installed to from pip? And also the path to the pyngcore.dll

[stenio]

Hi Christopher,

ngcore.dll is here:

C:\Users\User\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.12_qbz5n2kfra8p0\LocalCache\local-packages\Python312\site-packages\netgen

I can’t find pyngcore.dll. I have pyngcore.cp312-win_amd64.pyd in C:\Users\User\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.12_qbz5n2kfra8p0\LocalCache\local-packages\Python312\site-packages\pyngcore instead.

[stenio]

I fixed the missing modules adding their directories to %PATH%:

but still I get:

C:\Users\User>netgen Traceback (most recent call last): File "<frozen runpy>", line 198, in _run_module_as_main File "<frozen runpy>", line 88, in _run_code File "C:\Users\User\AppData\Local\Programs\Python\Python312\Scripts\netgen.exe\__main__.py", line 4, in <module> File "C:\Users\User\AppData\Local\Programs\Python\Python312\Lib\site-packages\netgen\__init__.py", line 98, in <module> from pyngcore import Timer File "C:\Users\User\AppData\Local\Programs\Python\Python312\Lib\site-packages\pyngcore\__init__.py", line 1, in <module> from .pyngcore import * ImportError: DLL load failed while importing pyngcore: A dynamic link library (DLL) initialization routine failed.

[stenio]

I made some progress setting the environment variable PYTHONPATH:

C:\Users\User>echo %PYTHONPATH%
C:\Users\User\AppData\Local\Programs\Python\Python312\Lib\site-packages\pyngcore;C:\Users\User\AppData\Local\Programs\Python\Python312\Lib\site-packages\netgen;C:\Users\User\AppData\Local\Programs\Python\Python312\Scripts;

C:\Users\User>echo %PATH%
C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Windows\System32\OpenSSH\;C:\Program Files\Microsoft SQL Server\150\Tools\Binn\;C:\Program Files\Microsoft SQL Server\Client SDK\ODBC\170\Tools\Binn\;C:\Program Files\dotnet\;C:\Users\User\AppData\Local\Programs\Python\Python312\Scripts\;C:\Users\User\AppData\Local\Programs\Python\Python312\;C:\Users\User\AppData\Local\Programs\Python\Launcher\;C:\Users\User\AppData\Local\Microsoft\WindowsApps;C:\Users\User\AppData\Local\Programs\Python\Python312\Scripts;C:\Users\User\AppData\Local\Programs\Python\Python312\Lib\site-packages\netgen;C:\Users\User\AppData\Local\Programs\Python\Python312;

C:\Users\User>netgen
Traceback (most recent call last):
  File "<frozen runpy>", line 198, in _run_module_as_main
  File "<frozen runpy>", line 88, in _run_code
  File "C:\Users\User\AppData\Local\Programs\Python\Python312\Scripts\netgen.exe\__main__.py", line 4, in <module>
    spec = importlib.util.spec_from_file_location(os.path.basename(f), os.path.abspath(f))
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\User\AppData\Local\Programs\Python\Python312\Lib\site-packages\netgen\__init__.py", line 98, in <module>
    from pyngcore import Timer
ImportError: DLL load failed while importing pyngcore: A dynamic link library (DLL) initialization routine failed.

[stenio]

I’ve reinstalled python 3.12 and the path now are

C:\Users\User\AppData\Local\Programs\Python\Python312\Lib\site-packages\pyngcore and
C:\Users\User\AppData\Local\Programs\Python\Python312\Lib\site-packages\netgen

The result is the same.

[stenio]

Perhaps the real problem is the absence of the pyngcore.dll file.