# I'm getting not a useful error when I try to start Slicer Jupyter kernel, how to debug?

**URL:** https://discourse.slicer.org/t/im-getting-not-a-useful-error-when-i-try-to-start-slicer-jupyter-kernel-how-to-debug/13530
**Category:** Support
**Created:** [September 17, 2020, 4:04pm UTC](https://discourse.slicer.org/t/im-getting-not-a-useful-error-when-i-try-to-start-slicer-jupyter-kernel-how-to-debug/13530 "2020-09-17T16:04:37Z")
**Posts on this page:** 1
**Showing post:** 6

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### Author: ![lassoan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/lassoan/32/13_2.png) [@lassoan](https://discourse.slicer.org/u/lassoan)
#### Post date: [September 17, 2020, 6:27pm UTC](https://discourse.slicer.org/t/im-getting-not-a-useful-error-when-i-try-to-start-slicer-jupyter-kernel-how-to-debug/13530/6 "2020-09-17T18:27:31Z")

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This is probably due to mixup of different Python environments.

We have encountered this problem when we simply wanted to run a terminal in Slicer’s Python environment:

> [@Crash when initializing app built and run from Ubuntu 20.04](https://discourse.slicer.org/t/crash-when-initializing-app-built-and-run-from-ubuntu-20-04/13265/8):
>
> Knowing that the crash occurred in libc is not very useful. Can you get a stack trace? This may help: [https://www.slicer.org/wiki/Documentation/Nightly/Developers/Tutorials/Debug\_Instructions#Analyze\_a\_segmentation\_fault](https://www.slicer.org/wiki/Documentation/Nightly/Developers/Tutorials/Debug_Instructions#Analyze_a_segmentation_fault) I’ve tried to start Slicer in gdb on Linux by following [these instructions](https://www.slicer.org/wiki/Documentation/Nightly/Developers/Tutorials/Debug_Instructions#GDB_debug_with_launch_arguments), I get the error below. When I try to debug using VS Code, I get the same error. osboxes@osboxes:~/D/Slicer-SuperBuild-Release/Slicer-build$ ./Slicer --launch /usr/bin/gnome-terminal Fatal Python error:…

@jcfr can you help us here? This user site packages/sysconfigdata issues has come up again. Should we add `Py_NoSiteFlag=1` in Slicer as suggested [here](https://stackoverflow.com/questions/49921336/sysconfigdata-error-when-trying-to-freeze-a-python-3-6-5-application) and [here](https://github.com/conda-forge/python-feedstock/issues/220)? (although I’m not sure how that could fix launching of a terminal or gdb)

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