[Bug Report] ./isaaclab.sh --install cannot work with isaacsim well

[Hit-Mickey]

It’s frustrating when a long-standing issue resurfaces, especially when you’ve followed the official documentation to the letter. It appears that while Isaac Lab "works," its installation process (likely due to the Conda environment setup) has inadvertently stripped or failed to link essential Python dependencies required by the Isaac Sim core extensions.

Here is the translation of your issue into English, formatted for a GitHub bug report:

Title: Persistent Dependency Issues: Isaac Sim Extensions Fail to Load Due to Missing psutil After Isaac Lab Installation (Related to #988)
Description
Despite this being related to issue #988 (reported in Sept 2024), I am still encountering a critical dependency break on May 6, 2026.

I followed the official binary installation guide. Initially, Isaac Sim was installed correctly and ran perfectly without any errors. However, during the Isaac Lab installation within a Conda environment, I encountered dependency conflicts similar to those mentioned in #988. Following the developer's suggestion that these errors could be ignored, I proceeded. While Isaac Lab finishes installation and "runs," the underlying Isaac Sim installation is now broken.

Steps to Reproduce
Install Isaac Sim (verified working).

Follow the Isaac Lab binary installation steps using a Conda environment.

Run ./isaaclab.sh --install.

Attempt to launch Isaac Sim or Isaac Lab.

Error Log
The following error occurs during startup, indicating that core Isaac Sim extensions (like omni.kit.test) can no longer find basic Python modules such as psutil:

Plaintext
2026-05-06T12:21:27Z [1,433ms] [Error] [omni.ext._impl.custom_importer] Failed to import python module omni.kit.test. Error: No module named 'psutil'. Traceback:
Traceback (most recent call last):
File ".../omni/ext/_impl/custom_importer.py", line 85, in import_module
return importlib.import_module(name)
...
File ".../omni/kit/test/reporter.py", line 23, in
import psutil
ModuleNotFoundError: No module named 'psutil'

2026-05-06T12:21:27Z [1,433ms] [Error] [carb.scripting-python.plugin] Exception: Extension python module: 'omni.kit.test' failed to load.
(Note: Many other extensions fail to load with similar "ModuleNotFoundError" or "failed to load" messages.)

Environment
OS: Ubuntu22.04 (Linux-x86_64)

Isaac Sim Version: 5.1.0

Isaac Lab Version: Main branch (as of 2026-05-06)

Python Version: 3.11 (via Conda)

How can i solve this problem?

thank you !

[d-kleine]

Same issue as #5481?

I think the issue is your Isaac Lab version. Main branch is already ahead of v3.0.0-beta, which requires Isaac Sim 6.0.0 and Python 3.12. Please try to checkout Isaac Lab v2.3.2 for Isaac Sim 5.1.0.

[Exokern]

ModuleNotFoundError: No module named 'psutil' from omni.kit.test usually means the Python environment that Kit is actually running with doesn’t have psutil installed (often due to mixing a Conda python/site-packages with the packaged Isaac Sim python).

A couple concrete checks that help pinpoint it:

1. Verify which interpreter isaaclab.sh is using:

./isaaclab.sh -p -c "import sys; print(sys.executable); import site; print(site.getsitepackages())"

2. Check whether psutil is installed in that interpreter:

./isaaclab.sh -p -m pip show psutil || true

If it’s missing, the lowest-risk fix is to install it into the same environment that isaaclab.sh launches:

./isaaclab.sh -p -m pip install psutil

If that works, it would be great to capture why the binary-install path leaves psutil absent (or why the Conda setup causes Kit to import from the wrong site-packages) so the docs/setup can avoid “Isaac Sim works until Isaac Lab install” confusion.

[RandomOakForest]

Thank you for posting this. The workaround would be to install via pip. Let us know if we can be of further help.