Unable to Release : System.NullReferenceException

Hi everyone,

I have a huge issue and I have no idea where it is coming from. I have to deploy really soon for a project, I hope someone will be able to help me !

I can’t release my project any more lately, and don’t really know why. I’ve searched but nothing helped.

Here is my output in project launcher :

Running AutomationTool...
[...]
********** BUILD COMMAND STARTED **********
Running: C:\Program Files\Epic Games\UE_4.20\Engine\Binaries\DotNET\UnrealBuildTool.exe ProjectName Win64 Shipping -Project=D:\UE4\ProjectName\ProjectName.uproject  D:\UE4\ProjectName\ProjectName.uproject -NoUBTMakefiles  -remoteini="D:\UE4\ProjectName" -skipdeploy -noxge -generatemanifest -NoHotReload -log="%AppData Folder%\Roaming\Unreal Engine\AutomationTool\Logs\C+Program+Files+Epic+Games+UE_4.20\UBT-ProjectName-Win64-Shipping.txt"
  Using Visual Studio 2017 14.15.26726 toolchain (C:\Program Files (x86)\Microsoft Visual Studio\2017\Community\VC\Tools\MSVC\14.15.26726) and Windows 10.0.17134.0 SDK (C:\Program Files (x86)\Windows Kits\10).
  Houdini Engine : Looking for Houdini Engine 16.5.571 in C:/Program Files/Side Effects Software/Houdini Engine 16.5.571
  Houdini Engine : Looking for Houdini 16.5.571 in D:\Program Files\Houdini
  Houdini Engine : Found Houdini in D:/Program Files/Houdini
  C:\Program Files\Epic Games\UE_4.20\Engine\Plugins\Runtime\HoudiniEngine\Source\HoudiniEngineRuntime\HoudiniEngineRuntime.Build.cs: warning: Referenced directory 'C:\Program Files\Epic Games\UE_4.20\Engine\Source\Plugins\Runtime\HoudiniEngine\Source\HoudiniEngineRuntime\Public\HAPI' does not exist.
  C:\Program Files\Epic Games\UE_4.20\Engine\Plugins\Runtime\HoudiniEngine\Source\HoudiniEngineRuntime\HoudiniEngineRuntime.Build.cs: warning: Referenced directory 'C:\Program Files\Epic Games\UE_4.20\Engine\Source\Plugins\Runtime\HoudiniEngine\Source\HoudiniEngineRuntime\Public' does not exist.
  D:\UE4\ProjectName\Plugins\WebSocket\Source\WebSocket\WebSocket.Build.cs: warning: Referenced directory 'C:\Program Files\Epic Games\UE_4.20\Engine\Source\WebSocket\Public' does not exist.
  ERROR: System.NullReferenceException: La référence d'objet n'est pas définie à une instance d'un objet.
            à UnrealBuildTool.UEBuildBinary.<>c.<SetupBinaryLinkEnvironment>b__35_0(FileItem Item) dans D:\Build\++UE4\Sync\Saved\CsTools\Engine\Source\Programs\UnrealBuildTool\Configuration\UEBuildBinary.cs:ligne 623
            à System.Linq.Enumerable.WhereSelectListIterator`2.MoveNext()
            à System.Linq.Enumerable.Any[TSource](IEnumerable`1 source, Func`2 predicate)
            à UnrealBuildTool.UEBuildBinary.SetupBinaryLinkEnvironment(ReadOnlyTargetRules Target, UEToolChain ToolChain, LinkEnvironment LinkEnvironment, CppCompileEnvironment CompileEnvironment, List`1 SharedPCHs, ISourceFileWorkingSet WorkingSet, ActionGraph ActionGraph) dans D:\Build\++UE4\Sync\Saved\CsTools\Engine\Source\Programs\UnrealBuildTool\Configuration\UEBuildBinary.cs:ligne 623
            à UnrealBuildTool.UEBuildBinary.Build(ReadOnlyTargetRules Target, UEToolChain ToolChain, CppCompileEnvironment CompileEnvironment, LinkEnvironment LinkEnvironment, List`1 SharedPCHs, ISourceFileWorkingSet WorkingSet, ActionGraph ActionGraph) dans D:\Build\++UE4\Sync\Saved\CsTools\Engine\Source\Programs\UnrealBuildTool\Configuration\UEBuildBinary.cs:ligne 196
            à UnrealBuildTool.UEBuildTarget.Build(BuildConfiguration BuildConfiguration, CPPHeaders Headers, List`1 OutputItems, List`1 UObjectModules, ISourceFileWorkingSet WorkingSet, ActionGraph ActionGraph, EHotReload HotReload, Boolean bIsAssemblingBuild) dans D:\Build\++UE4\Sync\Saved\CsTools\Engine\Source\Programs\UnrealBuildTool\Configuration\UEBuildTarget.cs:ligne 2357
            à UnrealBuildTool.UnrealBuildTool.RunUBT(BuildConfiguration BuildConfiguration, String[] Arguments, FileReference ProjectFile, Boolean bCatchExceptions) dans D:\Build\++UE4\Sync\Saved\CsTools\Engine\Source\Programs\UnrealBuildTool\UnrealBuildTool.cs:ligne 1480
         (see %AppData Folder%\Roaming\Unreal Engine\AutomationTool\Logs\C+Program+Files+Epic+Games+UE_4.20\UBT-ProjectName-Win64-Shipping.txt for full exception trace)
Took 3,431997s to run UnrealBuildTool.exe, ExitCode=5
ERROR: UnrealBuildTool failed. See log for more details. (%AppData Folder%\Roaming\Unreal Engine\AutomationTool\Logs\C+Program+Files+Epic+Games+UE_4.20\UBT-ProjectName-Win64-Shipping.txt)
       (see %AppData Folder%\Roaming\Unreal Engine\AutomationTool\Logs\C+Program+Files+Epic+Games+UE_4.20\Log.txt for full exception trace)
AutomationTool exiting with ExitCode=5 (5)
BUILD FAILED

Here is Log.Txt in the automation tool folder :
Log.txt on textshare

I tried deleting .vs/Binaries/Intermediate/Folder/.sln and regenerating, but it fixed nothing.

I think it might be coming from the HoudiniEngine Plugin, but it would really help if I could use it.

I can generate my project in Visual Studio Only in Development Editor and DebugGame Editor, but not Development, DebugGame and Shipping, so I have no way to release my project.

Any ideas ? I’m gonna continue try fixing it, but any help would be appreciated !

If you need more info, don’t hesitate to ask.

Thanks to anyone who took the time to read my issue.

EDIT : Ok I should have tried that earlier but when I remove the Houdini Engine plugin everything works fine… not really the fix I’m hoping for though…

We also have this problem. Thanks for sharing! +1

Thanks for this! We had the exact same problem.

Copy the HoudiniEngine folder from C:\Program Files\Side Effects Software\Houdini XX.Y.ZZZ\engine\unreal\4.XX to X:\Path\To\YourUE4Project\Plugins\Engine\Runtime\

I have the same problem, it worked, thx ! :slight_smile:

What on earth? This worked for me too. Is this documented somewhere on Side FX’s site?

Worked for me as well. A bit of a strange fix since the Houdini plugin has existed for quite some time, but the UBT still doesn’t detect it from the UE folder.

FYI I’ve reported this to Side FX and they are looking into it.

That issue was caused by a side effect of the UBT changes Epic introduced in UE4.20, and has been fixed in Houdini17.5.236 / 17.0.569.