# Unable to install extensions when Slicer is installed in system location

**URL:** <https://discourse.slicer.org/t/unable-to-install-extensions-when-slicer-is-installed-in-system-location/16588>\
**Category:** Support\
**Created:** [March 16, 2021, 11:56pm UTC](https://discourse.slicer.org/t/unable-to-install-extensions-when-slicer-is-installed-in-system-location/16588 "2021-03-16T23:56:49Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![jamesobutler](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/jamesobutler/32/7511_2.png) [@jamesobutler](https://discourse.slicer.org/u/jamesobutler)\
**Post date:** [March 16, 2021, 11:56pm UTC](https://discourse.slicer.org/t/unable-to-install-extensions-when-slicer-is-installed-in-system-location/16588/1 "2021-03-16T23:56:49Z")

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I have packaged and installed Slicer 4.13.0-2021-03-16 (from a local build) into a system location for all users at “C:/Program Files/Slicer 4.13.0-2021-03-16”, however I’m unable to install extensions.

The following message appears in the console output at startup.

```auto
"Failed to create extensions directory" "C:/Program Files/Slicer 4.13.0-2021-03-16/bin/../NA-MIC/Extensions-29780"

```

This message shows when opening the extensions manager.

 ![image](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/2/3/23f72e42b87596a585151903a1a2bd127c323bc5.png)

cc: @lassoan

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<div class="post-metadata">

**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:** [March 17, 2021, 4:27am UTC](https://discourse.slicer.org/t/unable-to-install-extensions-when-slicer-is-installed-in-system-location/16588/2 "2021-03-17T04:27:39Z")

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The main reason for installing extensions in the application home folder is that Python packages are installed there anyway, so the application home folder has to be writable (or Slicer has to be run as admin when you install extensions). It also allows making Slicer fully portable - see details [here](https://github.com/Slicer/Slicer/commit/008f8b9571452334e1d7a55cd5a13ec074905963).

If you want to allow any user to install extensions without admin rights and you only need to use extensions that don’t install Python packages at runtime then you can specify a custom extension install path folder in Slicer-NNN.ini file or revert to the old behavior of Slicer by specifying  
Slicer\_STORE\_SETTINGS\_IN\_APPLICATION\_HOME\_DIR:BOOL=OFF when configuring your Slicer build.

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<div class="post-metadata">

**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 13, 2021, 6:16pm UTC](https://discourse.slicer.org/t/unable-to-install-extensions-when-slicer-is-installed-in-system-location/16588/3 "2021-07-13T18:16:51Z")

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A post was split to a new topic: [Deploying slicer in an immutable container (Singularity)](https://discourse.slicer.org/t/deploying-slicer-in-an-immutable-container-singularity/18702)