I just upgraded to Blender 4.1 (Windows) and my addons, which say they work with 4.1, all fail because of a missing numpy.core._multiarray.umath.
I don't know how to use Python or NumPy, but I can see in the Blender folder that the "multiarray umath" file is there, and both Python and NumPy are the versions Blender says they should be.
I tried installing Python 3.11, Pip, and then NumPy on my computer and copying the files, but that did nothing. I assume it's a version issue with Python or NumPy since it works in 4.0.
I'll copy the error code below:
Traceback (most recent call last):
File "C:\Users\me\AppData\Roaming\Blender Foundation\Blender\4.1\scripts\modules\numpy\core\__init__.py", line 24, in <module>
from . import multiarray
File "C:\Users\me\AppData\Roaming\Blender Foundation\Blender\4.1\scripts\modules\numpy\core\multiarray.py", line 10, in <module>
from . import overrides
File "C:\Users\me\AppData\Roaming\Blender Foundation\Blender\4.1\scripts\modules\numpy\core\overrides.py", line 8, in <module>
from numpy.core._multiarray_umath import (
ModuleNotFoundError: No module named 'numpy.core._multiarray_umath'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "C:\Users\me\AppData\Roaming\Blender Foundation\Blender\4.1\scripts\modules\numpy\__init__.py", line 144, in <module>
from numpy.__config__ import show as show_config
File "C:\Users\me\AppData\Roaming\Blender Foundation\Blender\4.1\scripts\modules\numpy\__config__.py", line 4, in <module>
from numpy.core._multiarray_umath import (
File "C:\Users\me\AppData\Roaming\Blender Foundation\Blender\4.1\scripts\modules\numpy\core\__init__.py", line 50, in <module>
raise ImportError(msg)
ImportError:
IMPORTANT: PLEASE READ THIS FOR ADVICE ON HOW TO SOLVE THIS ISSUE!
Importing the numpy C-extensions failed. This error can happen for
many reasons, often due to issues with your setup or how NumPy was
installed.
We have compiled some common reasons and troubleshooting tips at:
https://numpy.org/devdocs/user/troubleshooting-importerror.html
Please note and check the following:
* The Python version is: Python3.11 from "C:\Program Files\Blender Foundation\Blender 4.1\4.1\python\bin\python.exe"
* The NumPy version is: "1.26.4"
and make sure that they are the versions you expect.
Please carefully study the documentation linked above for further help.
Original error was: No module named 'numpy.core._multiarray_umath'
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "C:\Program Files\Blender Foundation\Blender 4.1\4.1\scripts\modules\addon_utils.py", line 376, in enable
mod = importlib.import_module(module_name)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Program Files\Blender Foundation\Blender 4.1\4.1\python\Lib\importlib\__init__.py", line 126, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "<frozen importlib._bootstrap>", line 1204, in _gcd_import
File "<frozen importlib._bootstrap>", line 1176, in _find_and_load
File "<frozen importlib._bootstrap>", line 1147, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 690, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 940, in exec_module
File "<frozen importlib._bootstrap>", line 241, in _call_with_frames_removed
File "C:\Users\me\AppData\Roaming\Blender Foundation\Blender\4.1\scripts\addons\sectionbox\__init__.py", line 78, in <module>
modules = get_all_submodules(Path(__file__).parent)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\me\AppData\Roaming\Blender Foundation\Blender\4.1\scripts\addons\sectionbox\__init__.py", line 44, in get_all_submodules
return list(iter_submodules(directory, directory.name))
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\me\AppData\Roaming\Blender Foundation\Blender\4.1\scripts\addons\sectionbox\__init__.py", line 49, in iter_submodules
mod = importlib.import_module("." + name, package_name)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Program Files\Blender Foundation\Blender 4.1\4.1\python\Lib\importlib\__init__.py", line 126, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "<frozen importlib._bootstrap>", line 1204, in _gcd_import
File "<frozen importlib._bootstrap>", line 1176, in _find_and_load
File "<frozen importlib._bootstrap>", line 1147, in _find_and_load_unlocked
File "<frozen importlib._bootstrap>", line 690, in _load_unlocked
File "<frozen importlib._bootstrap_external>", line 940, in exec_module
File "<frozen importlib._bootstrap>", line 241, in _call_with_frames_removed
File "C:\Users\me\AppData\Roaming\Blender Foundation\Blender\4.1\scripts\addons\sectionbox\handlers.py", line 4, in <module>
from .utils.draw_handles import DrawHandles
File "C:\Users\me\AppData\Roaming\Blender Foundation\Blender\4.1\scripts\addons\sectionbox\utils\draw_handles.py", line 3, in <module>
import numpy as np
File "C:\Users\me\AppData\Roaming\Blender Foundation\Blender\4.1\scripts\modules\numpy\__init__.py", line 149, in <module>
raise ImportError(msg) from e
ImportError: Error importing numpy: you should not try to import numpy from
its source directory; please exit the numpy source tree, and relaunch
your python interpreter from there.
C:\Users\me\AppData\Roaming\Blender Foundation\Blender\4.1\scripts\modules\numpyand launching blender again (Make a backup beforehand) $\endgroup$print(np.__version__)and what python versionprint(sys.version). Mine is1.24.3and3.11.7respectively and it works fine on Blender 4.1.1. Try using that version or higher. $\endgroup$