Can't build project

Yo guys, when I try to build my project, I’am getting this error

UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:114][  0]LogWindows:Error: === Critical error: ===
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:115][  0]LogWindows:Error: 
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:115][  0]LogWindows:Error: Assertion failed: !DependencyIndex.IsNull() [File:D:\Build\++UE4+Release-4.13+Compile\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\SavePackage.cpp] [Line: 4366] 
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:115][  0]LogWindows:Error: Failed to find dependency index for WidgetBlueprintGeneratedClass /Game/ThirdPersonBP/Blueprints/PlayerWidget.PlayerWidget_C (Function /Game/ThirdPersonBP/Blueprints/ThirdPersonCharacter.ThirdP
UATHelper: Packaging (Windows (64-bit)): ersonCharacter_C:ExecuteUbergraph_ThirdPersonCharacter)
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:116][  0]LogWindows:Error: 
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:116][  0]LogWindows:Error: 
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:116][  0]LogWindows:Error: KERNELBASE.dll
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:116][  0]LogWindows:Error: UE4Editor-Core.dll!FOutputDeviceWindowsError::Serialize() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\private\windows\windowsplatformoutputdevices.cpp:103]
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:117][  0]LogWindows:Error: UE4Editor-Core.dll!FOutputDevice::Logf__VA() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\private\misc\outputdevice.cpp:94]
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:117][  0]LogWindows:Error: UE4Editor-Core.dll!FDebug::AssertFailed() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\private\misc\outputdevice.cpp:421]
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:118][  0]LogWindows:Error: UE4Editor-CoreUObject.dll!UPackage::Save() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\coreuobject\private\uobject\savepackage.cpp:4366]
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:118][  0]LogWindows:Error: UE4Editor-UnrealEd.dll!UEditorEngine::Save() [d:\build\++ue4+release-4.13+compile\sync\engine\source\editor\unrealed\private\editorengine.cpp:3953]
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:119][  0]LogWindows:Error: UE4Editor-UnrealEd.dll!UCookOnTheFlyServer::SaveCookedPackage() [d:\build\++ue4+release-4.13+compile\sync\engine\source\editor\unrealed\private\cookontheflyserver.cpp:2827]
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:119][  0]LogWindows:Error: UE4Editor-UnrealEd.dll!UCookOnTheFlyServer::TickCookOnTheSide() [d:\build\++ue4+release-4.13+compile\sync\engine\source\editor\unrealed\private\cookontheflyserver.cpp:2041]
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:120][  0]LogWindows:Error: UE4Editor-UnrealEd.dll!UCookCommandlet::NewCook() [d:\build\++ue4+release-4.13+compile\sync\engine\source\editor\unrealed\private\commandlets\cookcommandlet.cpp:1547]
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:120][  0]LogWindows:Error: UE4Editor-UnrealEd.dll!UCookCommandlet::Main() [d:\build\++ue4+release-4.13+compile\sync\engine\source\editor\unrealed\private\commandlets\cookcommandlet.cpp:844]
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:121][  0]LogWindows:Error: UE4Editor-Cmd.exe!FEngineLoop::PreInit() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\launch\private\launchengineloop.cpp:1828]
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:121][  0]LogWindows:Error: UE4Editor-Cmd.exe!GuardedMain() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\launch\private\launch.cpp:117]
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:121][  0]LogWindows:Error: UE4Editor-Cmd.exe!GuardedMainWrapper() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:126]
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:122][  0]LogWindows:Error: UE4Editor-Cmd.exe!WinMain() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:202]
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:122][  0]LogWindows:Error: UE4Editor-Cmd.exe!__scrt_common_main_seh() [f:\dd\vctools\crt\vcstartup\src\startup\exe_common.inl:264]
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:123][  0]LogWindows:Error: KERNEL32.DLL
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:123][  0]LogWindows:Error: ntdll.dll
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:123][  0]LogWindows:Error: ntdll.dll
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:123][  0]LogWindows:Error: 
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.10.19-14.32.23:123][  0]LogWindows:Error: end: stack for UAT
UATHelper: Packaging (Windows (64-bit)): CommandUtils.Run: Run: Took 51.5153329s to run UE4Editor-Cmd.exe, ExitCode=3
UATHelper: Packaging (Windows (64-bit)): Project.Cook: Cook failed. Deleting cooked data.
UATHelper: Packaging (Windows (64-bit)): Program.Main: ERROR: AutomationTool terminated with exception: AutomationTool.AutomationException: Cook failed. ---> AutomationTool.AutomationException: BUILD FAILED: Failed while running Cook for E:\Game Jam w Teatrze\ihavenoright2quite\ihavenoright2quite.uproject; see log C:\Users\Bogey\AppData\Roaming\Unreal Engine
\AutomationTool\Logs\E+UE4+Epic+Games+4.13\Cook-2016.10.19-16.32.58.txt
UATHelper: Packaging (Windows (64-bit)):    at AutomationTool.CommandUtils.RunCommandlet(FileReference ProjectName, String UE4Exe, String Commandlet, String Parameters)
UATHelper: Packaging (Windows (64-bit)):    at AutomationTool.CommandUtils.CookCommandlet(FileReference ProjectName, String UE4Exe, String[] Maps, String[] Dirs, String InternationalizationPreset, String[] CulturesToCook, String TargetPlatform, String Parameters)
UATHelper: Packaging (Windows (64-bit)):    at Project.Cook(ProjectParams Params)
UATHelper: Packaging (Windows (64-bit)):    --- End of inner exception stack trace ---
UATHelper: Packaging (Windows (64-bit)):    at Project.Cook(ProjectParams Params)
UATHelper: Packaging (Windows (64-bit)):    at BuildCookRun.DoBuildCookRun(ProjectParams Params)
UATHelper: Packaging (Windows (64-bit)):    at AutomationTool.BuildCommand.Execute()
UATHelper: Packaging (Windows (64-bit)):    at AutomationTool.Automation.Execute(List`1 CommandsToExecute, CaselessDictionary`1 Commands)
UATHelper: Packaging (Windows (64-bit)):    at AutomationTool.Automation.Process(String[] Arguments)
UATHelper: Packaging (Windows (64-bit)):    at AutomationTool.Program.MainProc(Object Param)
UATHelper: Packaging (Windows (64-bit)):    at AutomationTool.InternalUtils.RunSingleInstance(Func`2 Main, Object Param)
UATHelper: Packaging (Windows (64-bit)):    at AutomationTool.Program.Main()
UATHelper: Packaging (Windows (64-bit)): Program.Main: AutomationTool exiting with ExitCode=25 (Error_UnknownCookFailure)
UATHelper: Packaging (Windows (64-bit)): BUILD FAILED
PackagingResults:Error: Error Unknown Cook Failure

this i have if Im trying to launch it:
Assertion failed: !DependencyIndex.IsNull() [File:D:\Build++UE4+Release-4.13+Compile\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\SavePackage.cpp] [Line: 4366]
Failed to find dependency index for WidgetBlueprintGeneratedClass /Game/ThirdPersonBP/Blueprints/PlayerWidget.PlayerWidget_C (Function /Game/ThirdPersonBP/Blueprints/ThirdPersonCharacter.ThirdPersonCharacter_C:ExecuteUbergraph_ThirdPersonCharacter)

The whole problem is in this widget.

Hey B0gey,

I’ve investigated this issue, and it appears that it may be related to UE-30189, which has seemingly been resolved in 4.14.

If you’d like to provide your project, I can take a look and see if the issue is resolved in our internal branch and then provide you with a fix commit that you can merge in if you’re using a source build of the engine.

You can PM me a link to Dropbox or Google Drive where I can download the project here: https://forums.unrealengine.com/member.php?160394-Sean-Flint

Have a great day

Not resolved in 4.14 as I am having exact same issue:

Assertion failed: !DependencyIndex.IsNull() [File:D:\Build++UE4+Release-4.14+Compile\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\SavePackage.cpp] [Line: 4600]
UATHelper: Packaging (Windows (64-bit)): UE4Editor-Cmd: [2016.11.30-00.34.20:252][ 0]LogWindows:Error: Failed to find dependency index for WidgetBlueprint /Game/BluePrints/UI/videoLibrary_exp.videoLibrary_exp (MotionControllerMap_C /Game/VirtualRealityBP/Maps/MotionControllerMap.Default__MotionControllerMap_C)

what is the fix for it? I’ve removed that actor from all levels (kept source file) but still same thing is happening while cooking / building the project.

Hey Matt,

I’ve found a ticket in our system that appears to be related: Unreal Engine Issues and Bug Tracker (UE-30189)

If you take a look at your logs, see if you have the same callstack as the one listed in the ticket that I’ve linked above. If so, then it is likely that this is the issue that you are experiencing, which unfortunately does not have any fix at the current time.

Hi Guys,
I am having a bit of an issue that maybe u can help me with. I made a level on a mac and it all cooks and builds fine. When I move it over to a PC, I can run in in the editor, but cannot cook/build. I am at a total loss here and my options are to try to debug the problem and if no result, redo the whole MF thing from scratch. I did remove one UI widget that I had just in case and still no luck. Here is what my log states:

UATHelper: Cooking (Windows): UE4Editor-Cmd: [2017.03.16-11.28.52:139][ 0]LogWindows:Error: === Critical error: ===
UATHelper: Cooking (Windows): UE4Editor-Cmd: [2017.03.16-11.28.52:139][ 0]LogWindows:Error:
UATHelper: Cooking (Windows): UE4Editor-Cmd: [2017.03.16-11.28.52:139][ 0]LogWindows:Error: Assertion failed: !DependencyIndex.IsNull() [File:D:\Build++UE4+Release-4.15+Compile\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\SavePackage.cpp] [Line: 4889]
UATHelper: Cooking (Windows): UE4Editor-Cmd: [2017.03.16-11.28.52:139][ 0]LogWindows:Error: Failed to find dependency index for WidgetBlueprintGeneratedClass /Engine/VREditor/Tutorial/UMG/Buttons/SlideButtons.SlideButtons_C (ObjectProperty /Engine/VREditor/Tutorial/UMG/Slides/Option01/Option_01.Option_01_C:CheckForButtonEnabled.LocalButtonValue)

Hey robot mallorca,

Do me a favor and open up a new thread in the Packaging & Deployment section so that we can investigate this as a separate issue, as it’s likely that it’s not related to the original issue.

Thank you

Just did. thx.

I’m having this issue right now with latest UE 4.19.2, I’m new to Unreal and this is my first time trying to package a project so I don’t know when this issue started.