Unhandled exception: Exception: UBA executor is not expected to be invoked from a recursive UBT call.

Development Platform & Builds
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I’ve downloaded the Unreal Engine 5.8.0 source from Github, and after running Setup.bat and generating projects, I have the following error when trying to build with Visual Studio 2022 (17.14.35 June 2026)

1>Unhandled exception: Exception: UBA executor is not expected to be invoked from a recursive UBT call.
1>   at UnrealBuildTool.UBAExecutor.Init(IEnumerable`1 targetDescriptors, ILogger logger) in UnrealEngine\Engine\Source\Programs\UnrealBuildTool\Executors\UnrealBuildAccelerator\UBAExecutor.cs:line 315
1>   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
1>--- End of stack trace from previous location ---
1>   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
1>   at System.Threading.Tasks.Task.ExecuteWithThreadLocal(Task& currentTaskSlot, Thread threadPoolThread)
1>--- End of stack trace from previous location ---
1>   at UnrealBuildTool.UBAExecutor.ExecuteActionsAsync(IEnumerable`1 inputActions, ILogger logger) in UnrealEngine\Engine\Source\Programs\UnrealBuildTool\Executors\UnrealBuildAccelerator\UBAExecutor.cs:line 617
1>   at UnrealBuildTool.ActionGraph.InternalExecuteActions(ActionExecutor Executor, List`1 ActionsToExecute, ILogger Logger) in UnrealEngine\Engine\Source\Programs\UnrealBuildTool\Actions\ActionGraph.cs:line 435
1>   at UnrealBuildTool.ActionGraph.ExecuteActionsAsync(BuildConfiguration BuildConfiguration, List`1 ActionsToExecute, List`1 TargetDescriptors, ILogger Logger, ActionExecutor executor) in UnrealEngine\Engine\Source\Programs\UnrealBuildTool\Actions\ActionGraph.cs:line 413

There is some documentation that it is possible to disable UBA Executor with BuildConfiguration.xml:

<?xml version="1.0" encoding="utf-8" ?> false

However, investigating the source, it looks like in 5.8.0 this does nothing. In ExecutorFactory.cs (Engine\Source\Programs\UnrealBuildTool\Executors) the fallback is to create a UBA Executor, even if you’ve disabled it with the BuildConfiguration.xml

It’s possible I’ve missed some setup step somewhere, but generally running the Setup.bat and the building via Visual Studio has always worked for me. Any help would be appreciated.