Failed to import python module omni.isaac.core

Omniverse Isaac Sim
1

Please provide all relevant details below before submitting your post. This will help the community provide more accurate and timely assistance. After submitting, you can check the appropriate boxes. Remember, you can always edit your post later to include additional information if needed.

Isaac Sim Version

[ X] 4.2.0
4.1.0
4.0.0
2023.1.1
2023.1.0-hotfix.1
Other (please specify):

Isaac Lab Version (if applicable)

1.2
1.1
1.0
Other (please specify):

Operating System

Ubuntu 22.04
Ubuntu 20.04
Windows 11
Windows 10
Other (please specify):

GPU Information

  • Model: GIGABYTE RTX 3060 12GB
  • Driver Version: 566.36

Topic Description

When trying to boot it says it failed to import python module omni.isaac.core because specified module couldn’t be found. Which spirals causing a ton of extensions to fail to load because it can’t find the dependencies it needs.

Detailed Description

Since I first downloaded Isaac Sim I’ve always gotten a ton of errors when its booting, but it would boot seemingly fine so I just ignored it (I know that’s not the best idea but whatever). I went to install some extensions and noticed the extensions wouldn’t work because the dependencies couldn’t be found which caused me to look through and realize tons of extensions couldn’t load because it couldn’t find anything it needed. Then I looked at all the errors and they lined up to I deleted a reinstalled Isaac Sim figuring that that might fix the issue but it still persists.
(Describe the issue in detail, including what you were trying to do, what you expected to happen, and what actually happened)

Steps to Reproduce

  1. Install Isaac Sim 4.2.0
  2. Boot Isaac Sim 4.2.0

Error Messages

(If applicable, copy and paste any error messages you received)

2024-12-22 00:29:35 [2,383ms] [Error] [omni.ext._impl._internal] Failed to import python module omni.isaac.core from c:\users\user\appdata\local\ov\pkg\isaac-sim-4.2.0\exts\omni.isaac.core. Error: [WinError 126] The specified module could not be found. Error loading “c:/users/user/appdata/local/ov/pkg/isaac-sim-4.2.0/exts/omni.isaac.ml_archive/pip_prebundle/torch\lib\fbgemm.dll” or one of its dependencies… Traceback:
Traceback (most recent call last):
File “c:\users/user/appdata/local/ov/pkg/isaac-sim-4.2.0/kit/kernel/py\omni\ext_impl_internal.py”, line 187, in custom_importer
return import_public(ext_module.path, ext_module.name, reload_enabled)
File "c:\users/user/appdata/local/ov/pkg/isaac-sim-4.2.0/kit/kernel/py\carb\profiler_init.py", line 99, in wrapper
r = f(*args, **kwds)
File “c:\users/user/appdata/local/ov/pkg/isaac-sim-4.2.0/kit/kernel/py\omni\ext_impl_internal.py”, line 94, in import_public
module = import_module(module_name)
File "c:\users/user/appdata/local/ov/pkg/isaac-sim-4.2.0/kit/kernel/py\carb\profiler_init.py", line 99, in wrapper
r = f(*args, **kwds)
File “c:\users/user/appdata/local/ov/pkg/isaac-sim-4.2.0/kit/kernel/py\omni\ext_impl\custom_importer.py”, line 76, in import_module
return importlib.import_module(name)
File "c:\users\user\appdata\local\ov\pkg\isaac-sim-4.2.0\kit\python\lib\importlib_init.py", line 126, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File “”, line 1050, in _gcd_import
File “”, line 1027, in _find_and_load
File “”, line 1006, in _find_and_load_unlocked
File “”, line 688, in _load_unlocked
File “”, line 883, in exec_module
File “”, line 241, in _call_with_frames_removed
File “c:/users/user/appdata/local/ov/pkg/isaac-sim-4.2.0/exts/omni.isaac.core/omni/isaac/core/init.py”, line 11, in
from omni.isaac.core.physics_context.physics_context import PhysicsContext
File “c:/users/user/appdata/local/ov/pkg/isaac-sim-4.2.0/exts/omni.isaac.core/omni/isaac/core/physics_context/init.py”, line 9, in
from omni.isaac.core.physics_context.physics_context import PhysicsContext
File “c:/users/user/appdata/local/ov/pkg/isaac-sim-4.2.0/exts/omni.isaac.core/omni/isaac/core/physics_context/physics_context.py”, line 15, in
from omni.isaac.core.utils.prims import get_prim_at_path, get_prim_path, is_prim_path_valid
File “c:/users/user/appdata/local/ov/pkg/isaac-sim-4.2.0/exts/omni.isaac.core/omni/isaac/core/utils/prims.py”, line 24, in
from omni.isaac.core.utils.types import SDF_type_to_Gf
File “c:/users/user/appdata/local/ov/pkg/isaac-sim-4.2.0/exts/omni.isaac.core/omni/isaac/core/utils/types.py”, line 12, in
import torch
File “c:/users/user/appdata/local/ov/pkg/isaac-sim-4.2.0/exts/omni.isaac.ml_archive/pip_prebundle/torch/init.py”, line 148, in
raise err
OSError: [WinError 126] The specified module could not be found. Error loading “c:/users/user/appdata/local/ov/pkg/isaac-sim-4.2.0/exts/omni.isaac.ml_archive/pip_prebundle/torch\lib\fbgemm.dll” or one of its dependencies.

2024-12-22 00:29:35 [2,383ms] [Error] [carb.scripting-python.plugin] Exception: Extension python module: ‘omni.isaac.core’ in ‘c:\users\user\appdata\local\ov\pkg\isaac-sim-4.2.0\exts\omni.isaac.core’ failed to load.

At:
c:\users/user/appdata/local/ov/pkg/isaac-sim-4.2.0/kit/kernel/py\omni\ext_impl_internal.py(213): startup
c:\users/user/appdata/local/ov/pkg/isaac-sim-4.2.0/kit/kernel/py\omni\ext_impl_internal.py(328): startup_extension
PythonExtension.cpp::startup()(2):

2024-12-22 00:29:35 [2,383ms] [Error] [omni.ext.plugin] [ext: omni.isaac.core-3.19.5] Failed to startup python extension

Screenshots or Videos

(If applicable, add screenshots or links to videos that demonstrate the issue)

Additional Information

Pretty sure it only manages to boot by the power of god

What I’ve Tried

(Describe any troubleshooting steps you’ve already taken)
Looked through forums for other similar import issues and how to fix it but everything I found that might’ve been related was outdated.

Related Issues

(If you’re aware of any related issues or forum posts, please link them here)

Additional Context

(Add any other context about the problem here)
Isaac Sim seems to run fine weirdly enough, I had been learning it importing cad files and messing with a basic robot along with it moving around and had no issues.

2

I have the same issue. Isaac Sim 4.0.0 started up with no issues so this is an issue with the new version

3

@laveryjohn99 i figured out a hack to fix this. Something is wrong with the torch dlls in:

“C:\Users<user name>\AppData\Local\ov\pkg\isaacsim4.2.0\exts\omni.isaac.ml_archive\pip_prebundle\torch”

here is my fix:

  1. install isaac sim 4.0.0
  2. delete the folder “C:\Users<user name>\AppData\Local\ov\pkg\isaacsim4.2.0\exts\omni.isaac.ml_archive\pip_prebundle\torch”
  3. past instead of it, the same torch folder from isaac sim 4.0.0:
    “C:\Users<user name>\AppData\Local\ov\pkg\isaac-sim-4.0.0\exts\omni.isaac.ml_archive\pip_prebundle\torch”
1 Like
4

The Isaac Sim 4.20 that I installed on my old computer works, that was three months ago.
The same setup does not work on a new computer that I recently acquired.
This does indeed seem to be an Isaac Sim problem, something is wrong with the official Isaac Sim libraries.

5

This seems like a very temporary and volatile fix.
I hope we get an official fix soon.

6

Just discovered that this was actually a known windows issue and has an official and simple solution.

On some Windows systems, you may encounter an error like the following:

OSError: [WinError 126] The specified module could not be found. Error loading “C:\path\to\omni.isaac.ml_archive\pip_prebundle\torch\lib\fbgemm.dll” or one of its dependencies.

This issue is caused by missing build tools. To resolve it, install Visual Studio 2022 and then install ‘MSVC v143 - VS 2022 C++ x64/86 build tools’ through the Visual Studio interface.

Reference links:
https://docs.omniverse.nvidia.com/isaacsim/latest/known_issues.html#general

1 Like
7

This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.