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Postponed means that the issue was either a feature request or something that requires major refactoring on our side. Since that makes the issue not actionable in the close future we choose to close it as Postponed and add it on our internal roadmaps and technical debt pages instead.




Found in






Issue ID




Parallel Import does not work when importing models using External Materials mode

Asset - Database


How to reproduce:
1. Open the user attached "" project
2. Right-Click on "PgaTourEventGenesisScottishOpen.fbx" in the Assets folder
3. Select the Reimport option
4. Open the Console Window

Expected result: No errors
Actual result: "[Worker0] CreateFolder is not supported while importing out-of-process" is thrown

Reproducible with: 2021.2.0a18, 2021.3.1f1, 2022.1.0f1, 2022.2.0a11
Not reproducible with: 2019.4.38f1, 2020.3.34f1, 2021.2.0a17

- To consistently reproduce, if the materials folder gets created, delete it

  1. Resolution Note:

    Parallel import is still experimental and one of the things that doesn't work is the externalized materials mode which is a legacy feature. Because it is a legacy feature it may or may not be supported in parallel import mode depending on if it is possible to make it work in that setup. You can either disable parallel import or fix the importer settings of the models to not use the legacy mode.

Comments (2)

  1. AcidArrow

    Nov 23, 2023 07:56

    When will this stop being experimental? It has been a while. And does anyone use the internal materials workflow? It sucks, I do not understand how anyone is able to do anything without using the external material workflow.

  2. mikelortega

    Oct 30, 2023 16:06

    This is present in Unity 2022.3 LTS and that makes the Parallel Import useless. Many projects are upgraded from older Unity versions and those would throw the error. Also, some workflows do not benefit from embedded materials, sometimes it's wiser to share all materials as default mode. I think this should be fixed.

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