# Slicer crashes on startup due to SlicerVMTK extension

**URL:** <https://discourse.slicer.org/t/slicer-crashes-on-startup-due-to-slicervmtk-extension/47660>\
**Category:** Support\
**Tags:** vmtk\
**Created:** [July 17, 2026, 7:08pm UTC](https://discourse.slicer.org/t/slicer-crashes-on-startup-due-to-slicervmtk-extension/47660 "2026-07-17T19:08:28Z")\
**Posts on this page:** 7\
**Page:** 1

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**Author:** ![aabrown100-git](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/aabrown100-git/32/82187_2.png) [@aabrown100-git](https://discourse.slicer.org/u/aabrown100-git)\
**Post date:** [July 17, 2026, 7:08pm UTC](https://discourse.slicer.org/t/slicer-crashes-on-startup-due-to-slicervmtk-extension/47660/1 "2026-07-17T19:08:28Z")

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**Issue** : On Slicer 5.12.2, Slicer crashes on startup after restarting Slicer following installation of `SlicerVMTK`. The startup log shows module loading failures in `SlicerVMTK` due to unresolved dylib dependencies, including `libdcmjp2kcs.20.dylib` looking for `libopenjp2.7.dylib` and `libssl.1.1.dylib` referencing a bad install name (`/D/S/A/OpenSSL/libcrypto.1.1.dylib`). The crash happens during module instantiation while Slicer is loading extensions.

**Specs** : macOS Tahoe on 2026 MacBook Pro with M5 Pro chip

**Other** : I also tried installing `SlicerVMTK` on Slicer 5.10.0 and did not encounter any issues.

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**Author:** ![muratmaga](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/muratmaga/32/3622_2.png) [@muratmaga](https://discourse.slicer.org/u/muratmaga)\
**Post date:** [July 17, 2026, 7:20pm UTC](https://discourse.slicer.org/t/slicer-crashes-on-startup-due-to-slicervmtk-extension/47660/2 "2026-07-17T19:20:29Z")

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This macos specific, and related to this bug being tracked: [COMP: Update DCMTKcs to fix OpenJPEG over-linking on macOS by lassoan · Pull Request #9263 · Slicer/Slicer · GitHub](https://github.com/Slicer/Slicer/pull/9263)

Until that’s fixed and a new patch release is cut, your easiest option is to use windows or linux version.

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**Author:** ![aabrown100-git](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/aabrown100-git/32/82187_2.png) [@aabrown100-git](https://discourse.slicer.org/u/aabrown100-git)\
**Post date:** [July 17, 2026, 7:31pm UTC](https://discourse.slicer.org/t/slicer-crashes-on-startup-due-to-slicervmtk-extension/47660/3 "2026-07-17T19:31:42Z")

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> [@muratmaga](#):
>
> COMP: Update DCMTKcs to fix OpenJPEG over-linking on macOS by lassoan · Pull Request #9263 · Slicer/Slicer · GitHub

Thanks @muratmaga for the info. I see that PR is merged and I don’t see any linked issues. Is there other work to be done to fix this bug?

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**Author:** ![muratmaga](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/muratmaga/32/3622_2.png) [@muratmaga](https://discourse.slicer.org/u/muratmaga)\
**Post date:** [July 17, 2026, 7:33pm UTC](https://discourse.slicer.org/t/slicer-crashes-on-startup-due-to-slicervmtk-extension/47660/4 "2026-07-17T19:33:21Z")

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I do not know if there are any other work that needs to be done, but cutting a new release from scratch (like this) in itself takes a few days. Meanwhile I think the previews are fine (though I didn’t try it personnally).

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**Author:** ![ebrahim](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/ebrahim/32/13403_2.png) [@ebrahim](https://discourse.slicer.org/u/ebrahim)\
**Post date:** [July 17, 2026, 9:06pm UTC](https://discourse.slicer.org/t/slicer-crashes-on-startup-due-to-slicervmtk-extension/47660/5 "2026-07-17T21:06:16Z")

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The PR fixing the original issue is merged, but for some macOS-specific reason that I don’t yet understand there is a further problem that only applies to signed+notarized releases. The preview releases are unsigned, making them okay

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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:** [July 18, 2026, 3:27pm UTC](https://discourse.slicer.org/t/slicer-crashes-on-startup-due-to-slicervmtk-extension/47660/6 "2026-07-18T15:27:45Z")

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Sorry for the inconvenience. Until Slicer-5.12 is fixed, you can use a Slicer Preview Release (Slicer-5.13) on macOS if you need to use any extensions that contain C++ modules.

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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:** [July 18, 2026, 3:35pm UTC](https://discourse.slicer.org/t/slicer-crashes-on-startup-due-to-slicervmtk-extension/47660/7 "2026-07-18T15:35:22Z")

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I submitted an issue that we can mention at all related error reports and people can follow to get updates:

> <https://github.com/Slicer/Slicer/issues/9295>
>
> Extensions that contain compiled C++ code, such as MarkupsToModel and VMTK fail …on Slicer-5.12 on macOS.
> 
> See for example this error report:
> https://discourse.slicer.org/t/slicer-crashes-on-startup-due-to-slicervmtk-extension/47660