# Lighting Build Fail Swarm Error \[Interface:OpenJob\] Error: Invalid class

**URL:** <https://forums.unrealengine.com/t/lighting-build-fail-swarm-error-interface-openjob-error-invalid-class/482814>\
**Category:** Rendering\
**Tags:** light, swarm-agent, unreal-engine, question\
**Created:** [May 3, 2021, 6:57am UTC](https://forums.unrealengine.com/t/lighting-build-fail-swarm-error-interface-openjob-error-invalid-class/482814 "2021-05-03T06:57:49Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![anonymous\_user\_4f9036e6](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_4f9036e6](https://forums.unrealengine.com/u/anonymous_user_4f9036e6)\
**Post date:** [May 3, 2021, 6:57am UTC](https://forums.unrealengine.com/t/lighting-build-fail-swarm-error-interface-openjob-error-invalid-class/482814/1 "2021-05-03T06:57:49Z")

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Decided to continue work on one of my projects today and was unable to build the lighting.

I clicked “build lighting only” then got the “Lighting build failed.” error popup in the corner. The Message Log didn’t come up with anything, so I tried building the lighting on another level that already had the lighting built. I still got the same error. I opened swarm and looked at the logs tab

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**Author:** ![ahvaas](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/ahvaas/32/892705_2.png) [@ahvaas](https://forums.unrealengine.com/u/ahvaas)\
**Post date:** [August 9, 2022, 8:28am UTC](https://forums.unrealengine.com/t/lighting-build-fail-swarm-error-interface-openjob-error-invalid-class/482814/2 "2022-08-09T08:28:56Z")

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Here is the solution:

> [@SwarmAgent InvalidClass](https://forums.unrealengine.com/t/swarmagent-invalidclass/318432/2):
>
> After some time. I no get only Invalid Class exception 11:09:46: [CloseConnection] Closing orphaned Job () 11:09:46: [CloseConnection] Connection disconnected 1CE5C080 11:09:46: [GetMessage] Safely returning to 1CE5C080 with no message 11:09:46: [Interface:TryOpenConnection] Local connection established 11:09:46: [Interface:OpenJob] Error: Недопустимый класс 11:09:47: [MaintainConnections] Local connection has closed (1CE5C080) 11:09:47: [MaintainConnections] Removed connection 1CE5C080

Also read this article:

> **[WMI: Repository Corruption, or Not?](https://techcommunity.microsoft.com/t5/ask-the-performance-team/wmi-repository-corruption-or-not/ba-p/375484)**
>
> First published on TECHNET on Aug 08, 2014 ScenarioWindows Management Instrumentation failing due to repository being corruptedThe WMI Repository..

To fix this error I did this In PowerShell (Admin):

> net stop winmgmt /y  
> winmgmt /resetrepository  
> winmgmt /salvagerepository  
> winmgmt /verifyrepository

Done. The lighting now builds successfully.

PS: If some commands were not necessary - please correct me.

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**Author:** ![Vullnat](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@Vullnat](https://forums.unrealengine.com/u/Vullnat)\
**Post date:** [September 7, 2022, 5:03pm UTC](https://forums.unrealengine.com/t/lighting-build-fail-swarm-error-interface-openjob-error-invalid-class/482814/3 "2022-09-07T17:03:55Z")

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I followed these steps: [WMI corrupt - how to reinstall/repair?](https://documentation.n-able.com/N-central/troubleshooting/Content/kb/WMI-corrupt-how-to-reinstall-repair.htm), it works now. Thank you

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**Author:** ![Ashutosh](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@Ashutosh](https://forums.unrealengine.com/u/Ashutosh)\
**Post date:** [March 14, 2024, 3:04pm UTC](https://forums.unrealengine.com/t/lighting-build-fail-swarm-error-interface-openjob-error-invalid-class/482814/4 "2024-03-14T15:04:10Z")

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Thanks

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**Author:** ![moddelle](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@moddelle](https://forums.unrealengine.com/u/moddelle)\
**Post date:** [March 18, 2024, 11:50am UTC](https://forums.unrealengine.com/t/lighting-build-fail-swarm-error-interface-openjob-error-invalid-class/482814/5 "2024-03-18T11:50:58Z")

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MAAAN YOU ARE GOD!!! I tried everything to fix that error but it didn’t worked for me. Now with you I can package my game THAAANKS AGAIN!!!