Unknown error when packaging

Headless888 · September 15, 2026, 12:13pm

Hello! I am back here again after trying to unsuccessfully package my game.

(I’d export and send the log but I just don’t know how to do that)
My leading theory is that it has to do with plugins that are not up do date, but I’m not sure which ones I can safely disable, how to find out which are outdated or if this is even the case. Any and all help is appreciated. Thank you-

SparkleBoom · September 15, 2026, 5:16pm

To export the log you just have to navigate and take the file from the first line of your screenshot
C:\Users\Kalu\AppData\Roaming\Unreal Engine\AutomationTool\Logs\C+Program+Files+Epic+Games+UE_5.6\UBA-LAUNCH-Win64-Shipping.txt

Then you can just drag the file inside the reply and it will be uploaded (I just don’t remember if there is a file size limit).

The core error in your log is RulesError: Expecting to find a type to be declared in a module rules named 'Launch' in 'LAUNCHModuleRules'.

Are you using any third party plugin installed in the engine, like from Fab?
In this case, check if it is inside the marketplace folder that is required to work correctly.

Also, there is the possibility that the “Launch” module is include as “LAUNCH” is some Build.cs file, but it’s very strange.

In additon to that, there is this warning
Visual Studio 2022 compiler version 14.51... is not a preferred version. Please use 14.38...
I don’t think it should give you error like taht but it’s better to use the 14.38.33130 with ue 5.6

To do that you can go inside the project Saved/UnrealBuildTool folder and edit the BuildConfiguration.xml file to force Unreal using that version, like this below

<?xml version="1.0" encoding="utf-8" ?>
<Configuration xmlns="https://www.unrealengine.com/BuildConfiguration">
    <WindowsPlatform>
        <CompilerVersion>14.38.33130</CompilerVersion>
    </WindowsPlatform>
</Configuration>

You also need to check if you have it installed from the VisualStudio installer

Feel free to ping me back if you need support

DragonRelt · September 16, 2026, 4:21pm

There normally is not an unknown error, You need to scroll up in the list and see if there are any yellows, or red errors in your packaging. If there isnt anything then you may want to cook your setup before packaging.

Send a log of the yellow and red stuff as well, it helps.

Headless888 · September 24, 2026, 11:51am

Hello @SparkleBoom @DragonRelt Sorry it took me so log to get back to you, I got busy with work-

for Visual Studio I tried both updating it t the latest version and reverting to a previous one
here’s what I have it set up as:

unfortunately Forums doesn’t let me upload attachments so here’s the log in text:

Log started at 09/15/2026 14:10:18 (2026-09-15T12:10:18Z)
Resolved project argument C:\Users\Kalu\Documents\GMTK GAME JAM\LAUNCH\LAUNCH.uproject to C:\Users\Kalu\Documents\GMTK GAME JAM\LAUNCH\LAUNCH.uproject
No config file at C:\ProgramData\Unreal Engine\UnrealBuildTool\BuildConfiguration.xml
No config file at C:\Users\Kalu\AppData\Local\Unreal Engine\UnrealBuildTool\BuildConfiguration.xml
No config file at C:\Users\Kalu\Documents\Unreal Engine\UnrealBuildTool\BuildConfiguration.xml
Configuration will be read from:
C:\Users\Kalu\AppData\Roaming\Unreal Engine\UnrealBuildTool\BuildConfiguration.xml
Reading configuration file from cache (C:\Users\Kalu\Documents\GMTK GAME JAM\LAUNCH\Intermediate\Build\XmlConfigCache.bin): C:\Users\Kalu\AppData\Roaming\Unreal Engine\UnrealBuildTool\BuildConfiguration.xml
Reading configuration file from cache (C:\Users\Kalu\Documents\GMTK GAME JAM\LAUNCH\Intermediate\Build\XmlConfigCache.bin): C:\Users\Kalu\Documents\GMTK GAME JAM\LAUNCH\Saved\UnrealBuildTool\BuildConfiguration.xml
Reading configuration file from cache (C:\Users\Kalu\Documents\GMTK GAME JAM\LAUNCH\Intermediate\Build\XmlConfigCache.bin): C:\Users\Kalu\AppData\Local\UnrealEngine\Intermediate\Build\UnrealBuildTool.Env.BuildConfiguration.xml
Log file: C:\Users\Kalu\AppData\Roaming\Unreal Engine\AutomationTool\Logs\C+Program+Files+Epic+Games+UE_5.6\UBA-LAUNCH-Win64-Shipping.txt

Setting temp directory to ‘C:\Users\Kalu\AppData\Local\Temp\UnrealBuildTool\12c8af0c’
Registering build platform: UnrealBuildTool.AndroidPlatformFactory
Registering build platform: UnrealBuildTool.IOSPlatformFactory
Registering build platform: UnrealBuildTool.LinuxPlatformFactory
Registering build platform: UnrealBuildTool.MacPlatformFactory
Registering build platform: UnrealBuildTool.TVOSPlatformFactory
Registering build platform: UnrealBuildTool.WindowsPlatformFactory
Found Windows 10 SDK root at C:\Program Files (x86)\Windows Kits\10 (1)
Found Windows 10 SDK root at C:\Program Files (x86)\Windows Kits\10 (2)
Found Windows 10 SDK version 10.0.26100.0 at C:\Program Files (x86)\Windows Kits\10
Found Universal CRT version 10.0.26100.0 at C:\Program Files (x86)\Windows Kits\10
Found Windows 10 SDK version 10.0.28000.0 at C:\Program Files (x86)\Windows Kits\10
Found Universal CRT version 10.0.28000.0 at C:\Program Files (x86)\Windows Kits\10
Win64 Installed SDK(s): MinVersion_Sdk=10.0.19041.0, MaxVersion_Sdk=10.9.99999.0, CurrentVersion_Sdk=10.0.28000.0, Version_AutoSdk=10.0.22621.0, CurrentVersion_AutoSdk=
Registering build platform: Win64 - buildable: True
Registering build platform: UnrealBuildTool.VisionOSPlatformFactory
Command line: “C:\Program Files\Epic Games\UE_5.6\Engine\Binaries\DotNET\UnrealBuildTool\UnrealBuildTool.dll” LAUNCH Win64 Shipping “-Project=C:\Users\Kalu\Documents\GMTK GAME JAM\LAUNCH\LAUNCH.uproject” “-Manifest=C:\Users\Kalu\Documents\GMTK GAME JAM\LAUNCH\Intermediate\Build\Manifest.xml” “-remoteini=C:\Users\Kalu\Documents\GMTK GAME JAM\LAUNCH” -skipdeploy “-log=C:\Users\Kalu\AppData\Roaming\Unreal Engine\AutomationTool\Logs\C+Program+Files+Epic+Games+UE_5.6\UBA-LAUNCH-Win64-Shipping.txt”
Ignoring plugin ‘ModelingToolsEditorMode’ for platform/configuration
Ignoring plugin ‘GameplayInsights’ for platform/configuration
Ignoring plugin ‘ActorSequence’ for platform/configuration
Ignoring plugin ‘Paper2D’ for platform/configuration
Ignoring plugin ‘BackChannel’ for platform/configuration
Ignoring plugin ‘PythonScriptPlugin’ for platform/configuration
Ignoring plugin ‘ModelingToolsEditorMode’ for platform/configuration
Ignoring plugin ‘EOSShared’ for platform/configuration
Ignoring plugin ‘BaseCharacterFXEditor’ for platform/configuration
Ignoring plugin ‘MeshModelingToolsetExp’ for platform/configuration
Ignoring plugin ‘ContentBrowserFileDataSource’ for platform/configuration
Ignoring plugin ‘PixWinPlugin’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘ProjectLauncher’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘XCodeSourceCodeAccess’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘ContentBrowserFileDataSource’ for platform/configuration
Ignoring plugin ‘MeshModelingToolset’ for platform/configuration
Ignoring plugin ‘MeshModelingToolsetExp’ for platform/configuration
Ignoring plugin ‘Interchange’ due to unsupported platform
Ignoring plugin ‘PlanarCut’ for platform/configuration
Ignoring plugin ‘MeshModelingToolsetExp’ for platform/configuration
Ignoring plugin ‘LowLevelNetTrace’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘NFORDenoise’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘Interchange’ for platform/configuration
Ignoring plugin ‘EOSShared’ for platform/configuration
Ignoring plugin ‘InterchangeEditor’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘Interchange’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘MediaPlayerEditor’ for platform/configuration
Ignoring plugin ‘MediaPlayerEditor’ for platform/configuration
Ignoring plugin ‘MeshModelingToolset’ for platform/configuration
Ignoring plugin ‘InterchangeEditor’ for platform/configuration
Ignoring plugin ‘NNEDenoiser’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘OnlineSubsystemIOS’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘MsQuic’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘XInputDevice’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘Interchange’ for platform/configuration
Ignoring plugin ‘UbaController’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘PythonScriptPlugin’ for platform/configuration
Ignoring plugin ‘ModelingToolsEditorMode’ for platform/configuration
Ignoring plugin ‘EOSShared’ for platform/configuration
Ignoring plugin ‘BaseCharacterFXEditor’ for platform/configuration
Ignoring plugin ‘MeshModelingToolsetExp’ for platform/configuration
Ignoring plugin ‘ContentBrowserFileDataSource’ for platform/configuration
Ignoring plugin ‘GameplayInsights’ for platform/configuration
Ignoring plugin ‘PixWinPlugin’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘ProjectLauncher’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘XCodeSourceCodeAccess’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘ContentBrowserFileDataSource’ for platform/configuration
Ignoring plugin ‘MeshModelingToolset’ for platform/configuration
Ignoring plugin ‘MeshModelingToolsetExp’ for platform/configuration
Ignoring plugin ‘Interchange’ due to unsupported platform
Ignoring plugin ‘PlanarCut’ for platform/configuration
Ignoring plugin ‘MeshModelingToolsetExp’ for platform/configuration
Ignoring plugin ‘LowLevelNetTrace’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘NFORDenoise’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘Interchange’ for platform/configuration
Ignoring plugin ‘EOSShared’ for platform/configuration
Ignoring plugin ‘InterchangeEditor’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘Interchange’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘MediaPlayerEditor’ for platform/configuration
Ignoring plugin ‘MediaPlayerEditor’ for platform/configuration
Ignoring plugin ‘MeshModelingToolset’ for platform/configuration
Ignoring plugin ‘InterchangeEditor’ for platform/configuration
Ignoring plugin ‘NNEDenoiser’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘OnlineSubsystemIOS’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘MsQuic’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘XInputDevice’ due to unsupported platform in plugin descriptor
Ignoring plugin ‘Interchange’ for platform/configuration
Ignoring plugin ‘UbaController’ due to unsupported platform in plugin descriptor
Using ‘git status’ to determine working set for adaptive non-unity build (C:\Users\Kalu\Documents\GMTK GAME JAM\LAUNCH).
Creating makefile for LAUNCH (no existing makefile)
Skipping C:\Program Files\Epic Games\UE_5.6\Engine\Intermediate\Build\BuildRules\UE5Rules.dll: File is installed
Skipping C:\Program Files\Epic Games\UE_5.6\Engine\Intermediate\Build\BuildRules\UE5ProgramRules.dll: File is installed
Found VisualStudio2022 installation: C:\Program Files\Microsoft Visual Studio\18\Community (Product=Microsoft.VisualStudio.Product.Community, Version=18.10.12201.205)
Found Visual Studio toolchain: C:\Program Files\Microsoft Visual Studio\18\Community\VC\Tools\MSVC\14.51.36231 (Family=14.51.36231, FamilyRank=1, Version=14.51.36257, HostArchitecture=x64, ReleaseChannel=Latest, Architecture=x64, Error=False, Redist=C:\Program Files\Microsoft Visual Studio\18\Community\VC\Redist\MSVC\14.51.36231)
Available x64 toolchains (1):

C:\Program Files\Microsoft Visual Studio\18\Community\VC\Tools\MSVC\14.51.36231
(Family=14.51.36231, FamilyRank=1, Version=14.51.36257, HostArchitecture=x64, ReleaseChannel=Latest, Architecture=x64)
Visual Studio 2022 compiler version 14.51.36257 is not a preferred version. Please use the latest preferred version 14.38.33130
Building UnrealGame - LAUNCH - Win64 - Shipping
Expecting to find a type to be declared in a module rules named ‘Launch’ in ‘LAUNCHModuleRules, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null’. This type must derive from the ‘ModuleRules’ type defined by UnrealBuildTool.
CompilationResultException: Expecting to find a type to be declared in a module rules named ‘Launch’ in ‘LAUNCHModuleRules, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null’. This type must derive from the ‘ModuleRules’ type defined by UnrealBuildTool.
at UnrealBuildTool.RulesAssembly.CreateModuleRules(String ModuleName, ReadOnlyTargetRules Target, String ReferenceChain, ILogger Logger)
at UnrealBuildTool.UEBuildTarget.CreateModuleRulesAndSetDefaults(String ModuleName, String ReferenceChain, ILogger Logger)
at UnrealBuildTool.UEBuildTarget.FindOrCreateModuleByName(String ModuleName, String ReferenceChain, ILogger Logger)
at UnrealBuildTool.UEBuildTarget.FindOrCreateCppModuleByName(String ModuleName, String ReferenceChain, ILogger Logger)
at UnrealBuildTool.UEBuildTarget.SetupBinaries(ILogger Logger)
at UnrealBuildTool.UEBuildTarget.PreBuildSetup(ILogger Logger)
at UnrealBuildTool.UEBuildTarget.Create(TargetDescriptor Descriptor, Boolean bSkipRulesCompile, Boolean bForceRulesCompile, Boolean bUsePrecompiled, UnrealIntermediateEnvironment IntermediateEnvironment, ILogger Logger)
at UnrealBuildTool.UEBuildTarget.Create(TargetDescriptor Descriptor, BuildConfiguration BuildConfiguration, ILogger Logger)
at UnrealBuildTool.BuildMode.CreateMakefileAsync(BuildConfiguration BuildConfiguration, TargetDescriptor TargetDescriptor, ISourceFileWorkingSet WorkingSet, ILogger Logger)
at UnrealBuildTool.BuildMode.BuildAsync(List`1 TargetDescriptors, BuildConfiguration BuildConfiguration, ISourceFileWorkingSet WorkingSet, BuildOptions Options, FileReference WriteOutdatedActionsFile, ILogger Logger, Boolean bSkipPreBuildTargets, String ActionTypeFilter)
at UnrealBuildTool.BuildMode.ExecuteAsync(CommandLineArguments Arguments, ILogger Logger)
at UnrealBuildTool.UnrealBuildTool.Main(String ArgumentsArray)
WriteFileIfChanged() wrote 0 changed files of 1 requested writes.

Timeline:
[ 0.000] +0.553 Main
0.121 [ 0.120] +0.129 Apply XmlConfig
0.347 [ 0.347] +0.205 RegisterPlatforms
[ 0.553] +0.940 BuildMode
0.553 [ 0.000] +0.503
1.056 [ 0.503] +0.430 Creating MakeFile for LAUNCH
1.488 [ 0.934] +0.006 Saving caches
[ 1.513] +0.000 TelemetryService.FlushEvents
[ 1.514]

Result: Failed (RulesError)
Total execution time: 1.51 seconds

Headless888 · September 24, 2026, 12:11pm

Here’s the whole output log (I checked it to be all messages, errors etc in the filters..) can’t see any warnings..

Headless888 · September 24, 2026, 12:18pm

It seems that the error is.. Rules error? But I can’t figure out how to find the LAUNCHModuleRules much less how to fix it? I’m very bad at all of the technical aspects of gamedev still so I’m just at a loss so far and very confused-

SparkleBoom · September 24, 2026, 1:04pm

@Headless888
Ok probably I got the issue annnnd it’s pretty funny

Looking at the log, your project name is LAUNCH (C:\Users\Kalu\Documents\GMTK GAME JAM\LAUNCH) and then the module and the class LAUNCH are named after it (LAUNCH.Build.cs and public class LAUNCH: ModuleRules).
Unreal is having a conflict because “Launch” is an internal startup module that already uses this name.

It’s a C++ project right?
If so, you can try to rename it (it’s a bit of work, remember to make a backup or if you are using a version control make a branch form a safe point)

To fully resolve the issue, you need to rename the .uproject file, the project folder as well and the C++ modules.

Rename the Project Folder and .uproject File:
- Close Unreal and Visual Studio.
- Go to your project directory (C:\Users\Kalu\Documents\GMTK GAME JAM\).
- Rename the main project folder from LAUNCH to something else (e.g., LaunchGame).
- Inside that folder, rename LAUNCH.uproject to match the new folder name (e.g., LaunchGame.uproject).
Update the .uproject Text Content:
- Open your newly renamed .uproject file with a text editor.
- Check the JSON code inside and make sure any module name references match your new project name, then save the file.
  
  image367×123 2.12 KB
Rename Source Files and Modules:
- Go into the Source folder.
- Rename LAUNCH.Build.cs (and any LAUNCH.cpp/LAUNCH.h files) to match your new name (e.g., LaunchGame.Build.cs).
- Open the target.cs file in your code editor and update the class declaration to match (e.g., public class LaunchGame: ModuleRules).
Regenerate Project Files:
- Right-click your new .uproject file and select “Generate Visual Studio project files”.
- Open the project and try packaging again

Headless888 · September 29, 2026, 12:38pm

Hi! (oh heck sorry missed this one too I gotta be better about checking my forums replies-) I’m only having issue with the 4th step.. I may be dumb but “Generate Visual Studio project files” just doesn’t come up as an option.
And also when I open the .uproject file in a text editor there isn’t any module name references that I can see at all-

but I did just open it with Notepad so maybe that’s also silly and I need another text editor?- thank you again for all your help!!

SparkleBoom · September 29, 2026, 12:44pm

Don’t worry mate, you’re not dumb at all!

If you don’t see the “Modules” there it’s not a problem, it’s just means that your project have no code (engine apart) but only Blueprints.

You can just try to open the project skipping the 4th step and see if it works

Let me know

Headless888 · September 29, 2026, 12:58pm

ok so it seems like the problem is still there.. I’m not sure what to do about it though..
it’s still the same module rules thing

side note: thank you so much for all of your help so far, this is all new territory for me so this is greatly appreciated-

SparkleBoom · September 29, 2026, 1:03pm

mmmm try this

Close Unreal
Go inside the root folder of the project
Remove completly the Intermediate,Save and Binaries folder if any
Reopen Unreal and retry packaging

and no problem again for the help, we all begin like this

Headless888 · September 29, 2026, 1:20pm

ok so something seems to be happening, but also as I opened the project it also generated a new “LAUNCH” folder with just the “DerivedDataCache” inside

so that must mean I missed renaming something? but I’m not sure what and it doesn’t seem to be affecting the build/packaging anymore.. which is nice but I still don’t quite understand what’s happening (ran into another issue while trying to build rn but i think I know how to solve that one, so I’ll get back to you after I do that and let you know if it actually all works or not)

SparkleBoom · September 29, 2026, 1:24pm

This folder should not be an issue since it’s probably be created from some cache data in the local App data folder after the project rename

Can you just share a screen of the folder structure you have now?
Basically all the stuff inside GMTK GAME JAM

Waiting for the result

Headless888 · September 29, 2026, 1:27pm

please ignore all of the unorganized blender files-

(my github is freaking out as well but its fiiiine-)

SparkleBoom · September 29, 2026, 1:29pm

It looks fine lets see if it works after you solve yours stuff

Headless888 · September 29, 2026, 4:00pm

It all works!!

thank you again so so much for (on multiple occasions) taking the time to come and help me with this! I genuinely cant thank you enough
I’ll be better about naming my projects lol (and now know what files can be safely regenerated I needed-)

last little question: do you think I can safely move the DerivedDataCache folder into my renamed project folder or should I just leave it if it’s not causing problems-

SparkleBoom · September 29, 2026, 4:30pm

Let’s go!!! Happy to hear that!

Regarding the DerivedCache you can just leave that as it is and also i think that DerivedCache should be empty (the one inside the old project name folder)