# Buld failure dues to cesium in ue 5.6.1

**URL:** <https://community.cesium.com/t/buld-failure-dues-to-cesium-in-ue-5-6-1/44693>\
**Category:** Cesium for Unreal\
**Created:** [December 24, 2025, 8:43am UTC](https://community.cesium.com/t/buld-failure-dues-to-cesium-in-ue-5-6-1/44693 "2025-12-24T08:43:48Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![mans\_not\_cold](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/mans_not_cold/32/28173_2.png) [@mans\_not\_cold](https://community.cesium.com/u/mans_not_cold)\
**Post date:** [December 24, 2025, 8:43am UTC](https://community.cesium.com/t/buld-failure-dues-to-cesium-in-ue-5-6-1/44693/1 "2025-12-24T08:43:48Z")

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I’m creating an arch viz project using cesium but recently I’ve started to run into a problem where when i package my project it always fails at a specific point right after garbage collection.

Here is the failure im dealing with;

UATHelper: Packaging (Windows): LogWindows: Error: begin: stack for UAT  
UATHelper: Packaging (Windows): LogWindows: Error: === Critical error: ===  
UATHelper: Packaging (Windows): LogWindows: Error:  
UATHelper: Packaging (Windows): LogWindows: Error: Fatal error!  
UATHelper: Packaging (Windows): LogWindows: Error:  
UATHelper: Packaging (Windows): LogWindows: Error: Unhandled Exception: EXCEPTION\_ACCESS\_VIOLATION reading address 0x0000000000000020  
UATHelper: Packaging (Windows): LogWindows: Error:  
UATHelper: Packaging (Windows): LogWindows: Error: [Callstack] 0x00007ff9b9dbfb61 UnrealEditor-CesiumRuntime.dll!Cesium3DTilesSelection::TilesetContentLoader::setOwner()   
UATHelper: Packaging (Windows): LogWindows: Error: [Callstack] 0x00007ff9b9dc09b1 UnrealEditor-CesiumRuntime.dll!async::detail::task\_func\<async::detail::inline\_scheduler\_impl,async::detail::continuation\_exec\_func\<async::detail::inline\_scheduler\_impl,async::taskCesium3DTilesSelection::TileLoadResult,std::tupleCesium3DTilesSelection::TileContentLoadInfo,Cesium3DTilesSelection::TileLoadResult,`CesiumAsync::Future<Cesium3DTilesSelection::TileLoadResult>::thenPassThrough<Cesium3DTilesSelection::TileContentLoadInfo>'::`2’::\<lambda\_1\>,std::integral\_constant\<bool,1\>,0\>,std::tuple\<Cesium3DTilesSele  
ction::TileContentLoadInfo,Cesium3DTilesSelection::TileLoadResult\> \>::destroy()   
UATHelper: Packaging (Windows): LogWindows: Error: [Callstack] 0x00007ff9b9e1ad35 UnrealEditor-CesiumRuntime.dll!CesiumAsync::CesiumImpl::QueuedScheduler::dispatchInternal()   
UATHelper: Packaging (Windows): LogWindows: Error: [Callstack] 0x00007ff9b9e1adaa UnrealEditor-CesiumRuntime.dll!CesiumAsync::CesiumImpl::QueuedScheduler::dispatchQueuedContinuations()   
UATHelper: Packaging (Windows): LogWindows: Error: [Callstack] 0x00007ff9b91b69e1 UnrealEditor-CesiumRuntime.dll!ACesium3DTileset::IsReadyForFinishDestroy() [D:\build\U5M\Sync\LocalBuilds\PluginTemp\HostProject\Plugins\CesiumForUnreal\Source\CesiumRuntime\Private\Cesium3DTileset.cpp:2301]  
UATHelper: Packaging (Windows): LogWindows: Error: [Callstack] 0x00007ff9f28a7eac UnrealEditor-CoreUObject.dll!UnknownFunction   
UATHelper: Packaging (Windows): LogWindows: Error: [Callstack] 0x00007ff9f28a8c80 UnrealEditor-CoreUObject.dll!UnknownFunction   
UATHelper: Packaging (Windows): LogWindows: Error: [Callstack] 0x00007ff9f2817e77 UnrealEditor-CoreUObject.dll!UnknownFunction   
UATHelper: Packaging (Windows): LogWindows: Error: [Callstack] 0x00007ff9f28b24e8 UnrealEditor-CoreUObject.dll!UnknownFunction   
UATHelper: Packaging (Windows): LogWindows: Error: [Callstack] 0x00007ff9f28555c9 UnrealEditor-CoreUObject.dll!UnknownFunction   
UATHelper: Packaging (Windows): LogWindows: Error: [Callstack] 0x00007ff9eca5664a UnrealEditor-UnrealEd.dll!UnknownFunction   
UATHelper: Packaging (Windows): LogWindows: Error: [Callstack] 0x00007ff9eca9994d UnrealEditor-UnrealEd.dll!UnknownFunction   
UATHelper: Packaging (Windows): LogWindows: Error: [Callstack] 0x00007ff9eca5a69a UnrealEditor-UnrealEd.dll!UnknownFunction   
UATHelper: Packaging (Windows): LogWindows: Error: [Callstack] 0x00007ff9eca76c83 UnrealEditor-UnrealEd.dll!UnknownFunction   
UATHelper: Packaging (Windows): LogWindows: Error: [Callstack] 0x00007ff74d0f8fa0 UnrealEditor-Cmd.exe!UnknownFunction   
UATHelper: Packaging (Windows): LogWindows: Error: [Callstack] 0x00007ff74d0ee39c UnrealEditor-Cmd.exe!UnknownFunction   
UATHelper: Packaging (Windows): LogWindows: Error: [Callstack] 0x00007ff74d0ee6ba UnrealEditor-Cmd.exe!UnknownFunction   
UATHelper: Packaging (Windows): LogWindows: Error: [Callstack] 0x00007ff74d0f209e UnrealEditor-Cmd.exe!UnknownFunction   
UATHelper: Packaging (Windows): LogWindows: Error: [Callstack] 0x00007ff74d104e44 UnrealEditor-Cmd.exe!UnknownFunction   
UATHelper: Packaging (Windows): LogWindows: Error: [Callstack] 0x00007ff74d107466 UnrealEditor-Cmd.exe!UnknownFunction   
UATHelper: Packaging (Windows): LogWindows: Error: [Callstack] 0x00007ffa7fa1e8d7 KERNEL32.DLL!UnknownFunction   
UATHelper: Packaging (Windows): LogWindows: Error:  
UATHelper: Packaging (Windows): LogWindows: Error: end: stack for UAT  
PackagingResults: Error: begin: stack for UAT  
PackagingResults: Error: === Critical error: ===  
PackagingResults: Error: Fatal error!  
PackagingResults: Error: Unhandled Exception: EXCEPTION\_ACCESS\_VIOLATION reading address 0x0000000000000020  
PackagingResults: Error: [Callstack] 0x00007ff9b9dbfb61 UnrealEditor-CesiumRuntime.dll!Cesium3DTilesSelection::TilesetContentLoader::setOwner()   
PackagingResults: Error: [Callstack] 0x00007ff9b9dc09b1 UnrealEditor-CesiumRuntime.dll!async::detail::task\_func\<async::detail::inline\_scheduler\_impl,async::detail::continuation\_exec\_func\<async::detail::inline\_scheduler\_impl,async::taskCesium3DTilesSelection::TileLoadResult,std::tupleCesium3DTilesSelection::TileContentLoadInfo,Cesium3DTilesSelection::TileLoadResult,`CesiumAsync::Future<Cesium3DTilesSelection::TileLoadResult>::thenPassThrough<Cesium3DTilesSelection::TileContentLoadInfo>'::`2’::\<lambda\_1\>,std::integral\_constant\<bool,1\>,0\>,std::tuple\<Cesium3DTilesSelection::TileContentLoadInfo  
,Cesium3DTilesSelection::TileLoadResult\> \>::destroy()   
PackagingResults: Error: [Callstack] 0x00007ff9b9e1ad35 UnrealEditor-CesiumRuntime.dll!CesiumAsync::CesiumImpl::QueuedScheduler::dispatchInternal()   
PackagingResults: Error: [Callstack] 0x00007ff9b9e1adaa UnrealEditor-CesiumRuntime.dll!CesiumAsync::CesiumImpl::QueuedScheduler::dispatchQueuedContinuations()   
PackagingResults: Error: [Callstack] 0x00007ff9b91b69e1 UnrealEditor-CesiumRuntime.dll!ACesium3DTileset::IsReadyForFinishDestroy() [D:\build\U5M\Sync\LocalBuilds\PluginTemp\HostProject\Plugins\CesiumForUnreal\Source\CesiumRuntime\Private\Cesium3DTileset.cpp:2301]  
PackagingResults: Error: [Callstack] 0x00007ff9f28a7eac UnrealEditor-CoreUObject.dll!UnknownFunction   
PackagingResults: Error: [Callstack] 0x00007ff9f28a8c80 UnrealEditor-CoreUObject.dll!UnknownFunction   
PackagingResults: Error: [Callstack] 0x00007ff9f2817e77 UnrealEditor-CoreUObject.dll!UnknownFunction   
PackagingResults: Error: [Callstack] 0x00007ff9f28b24e8 UnrealEditor-CoreUObject.dll!UnknownFunction   
PackagingResults: Error: [Callstack] 0x00007ff9f28555c9 UnrealEditor-CoreUObject.dll!UnknownFunction   
PackagingResults: Error: [Callstack] 0x00007ff9eca5664a UnrealEditor-UnrealEd.dll!UnknownFunction   
PackagingResults: Error: [Callstack] 0x00007ff9eca9994d UnrealEditor-UnrealEd.dll!UnknownFunction   
PackagingResults: Error: [Callstack] 0x00007ff9eca5a69a UnrealEditor-UnrealEd.dll!UnknownFunction   
PackagingResults: Error: [Callstack] 0x00007ff9eca76c83 UnrealEditor-UnrealEd.dll!UnknownFunction   
PackagingResults: Error: [Callstack] 0x00007ff74d0f8fa0 UnrealEditor-Cmd.exe!UnknownFunction   
PackagingResults: Error: [Callstack] 0x00007ff74d0ee39c UnrealEditor-Cmd.exe!UnknownFunction   
PackagingResults: Error: [Callstack] 0x00007ff74d0ee6ba UnrealEditor-Cmd.exe!UnknownFunction   
PackagingResults: Error: [Callstack] 0x00007ff74d0f209e UnrealEditor-Cmd.exe!UnknownFunction   
PackagingResults: Error: [Callstack] 0x00007ff74d104e44 UnrealEditor-Cmd.exe!UnknownFunction   
PackagingResults: Error: [Callstack] 0x00007ff74d107466 UnrealEditor-Cmd.exe!UnknownFunction   
PackagingResults: Error: [Callstack] 0x00007ffa7fa1e8d7 KERNEL32.DLL!UnknownFunction

Any ideas why id be running into this problem and a solution would be great!

Thank you

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**Author:** ![Kevin\_Ring](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/kevin_ring/32/2003_2.png) [@Kevin\_Ring](https://community.cesium.com/u/Kevin_Ring)\
**Post date:** [December 29, 2025, 11:25am UTC](https://community.cesium.com/t/buld-failure-dues-to-cesium-in-ue-5-6-1/44693/2 "2025-12-29T11:25:56Z")

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Hi @mans_not_cold, welcome to the community!

Sorry to hear you’re having trouble. I don’t know offhand what would cause that. To help narrow down the problem, can you tell us what version of Cesium for Unreal you’re using? It’s in the lower-right corner of the Cesium panel. Did you happen to upgrade shortly before this happened? If you’re not already running the latest, can you try upgrading and see if that helps? Can you reproduce this in a clean project, or does it only happen in your own? Anything you can do to help us reproduce this problem ourselves will drastically increase the chances that we’re able to fix it.

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**Author:** ![vin\_wong](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/vin_wong/32/32822_2.png) [@vin\_wong](https://community.cesium.com/u/vin_wong)\
**Post date:** [January 23, 2026, 12:56am UTC](https://community.cesium.com/t/buld-failure-dues-to-cesium-in-ue-5-6-1/44693/3 "2026-01-23T00:56:22Z")

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You can try version 2.19.0. The new version causes an error, and I don’t know why yet.