Crash on opening Widget Blueprint

I have tried this in multiple versions of the engine. Currently I am on 4.5.
This problem is specific to one project.

Whenever I try open a blueprint widget, the editor crashes. Even if I make a new widget blueprint and try open it, it crashes as well. If I copy the assets into a new project they open fine.

Here is the error message I get:

Assertion failed: IsValid() [File:C:\Unreal45\Unreal\Engine\Source\Runtime\Core\Public\Templates\SharedPointer.h] [Line: 658] 



KERNELBASE.dll!UnknownFunction (0x000007fefd93940d) + 0 bytes [UnknownFile:0]
UE4Editor-Core.dll!FOutputDeviceWindowsError::Serialize() (0x000007fede5b9ecd) + 0 bytes [c:\unreal45\unreal\engine\source\runtime\core\private\windows\windowsplatformoutputdevices.cpp:95]
UE4Editor-Core.dll!FOutputDevice::Logf__VA() (0x000007fede455b08) + 159 bytes [c:\unreal45\unreal\engine\source\runtime\core\private\misc\outputdevice.cpp:145]
UE4Editor-Core.dll!FDebug::AssertFailed() (0x000007fede4388c2) + 62 bytes [c:\unreal45\unreal\engine\source\runtime\core\private\misc\outputdevice.cpp:220]
UE4Editor-UMGEditor.dll!FWidgetBlueprintEditor::InitWidgetBlueprintEditor() (0x000007fed4cedb8e) + 44 bytes [c:\unreal45\unreal\engine\source\editor\umgeditor\private\widgetblueprinteditor.cpp:67]
UE4Editor-UMGEditor.dll!FAssetTypeActions_WidgetBlueprint::OpenAssetEditor() (0x000007fed4d11df1) + 24 bytes [c:\unreal45\unreal\engine\source\editor\umgeditor\private\assettypeactions_widgetblueprint.cpp:32]
UE4Editor-UnrealEd.dll!FAssetEditorManager::OpenEditorForAsset() (0x000007fed9ac61e2) + 152 bytes [c:\unreal45\unreal\engine\source\editor\unrealed\private\toolkits\asseteditormanager.cpp:288]
UE4Editor-UMGEditor.dll!FAssetTypeActions_Base::AssetsActivated() (0x000007fed4c800c9) + 0 bytes [c:\unreal45\unreal\engine\source\developer\assettools\public\assettypeactions_base.h:36]
UE4Editor-ContentBrowser.dll!SContentBrowser::OnAssetsActivated() (0x000007feceaac3c4) + 0 bytes [c:\unreal45\unreal\engine\source\editor\contentbrowser\private\scontentbrowser.cpp:1362]
UE4Editor-ContentBrowser.dll!TBaseSPMethodDelegateInstance_TwoParams<SContentBrowser,void,TArray<FAssetData,FDefaultAllocator> const & __ptr64,enum EAssetTypeActivationMethod::Type,0>::Execute() (0x000007fecea38163) + 18 bytes [c:\unreal45\unreal\engine\source\runtime\core\public\delegates\delegateinstancesimpl.inl:161]
UE4Editor-ContentBrowser.dll!TBaseSPMethodDelegateInstance_TwoParams<SContentBrowser,void,TArray<FAssetData,FDefaultAllocator> const & __ptr64,enum EAssetTypeActivationMethod::Type,0>::ExecuteIfSafe() (0x000007fecea41d08) + 15 bytes [c:\unreal45\unreal\engine\source\runtime\core\public\delegates\delegateinstancesimpl.inl:171]
UE4Editor-ContentBrowser.dll!SAssetView::OnListMouseButtonDoubleClick() (0x000007feceab7e04) + 43 bytes [c:\unreal45\unreal\engine\source\editor\contentbrowser\private\sassetview.cpp:3125]
UE4Editor-ContentBrowser.dll!TBaseSPMethodDelegateInstance_OneParam<SAssetView,void,TSharedPtr<FAssetViewItem,0>,0>::Execute() (0x000007fecea314b6) + 41 bytes [c:\unreal45\unreal\engine\source\runtime\core\public\delegates\delegateinstancesimpl.inl:161]
UE4Editor-ContentBrowser.dll!TBaseSPMethodDelegateInstance_OneParam<SAssetView,void,TSharedPtr<FAssetViewItem,0>,0>::ExecuteIfSafe() (0x000007fecea3fd6b) + 38 bytes [c:\unreal45\unreal\engine\source\runtime\core\public\delegates\delegateinstancesimpl.inl:171]
UE4Editor-ContentBrowser.dll!TBaseDelegate_OneParam<void,TSharedPtr<FAssetViewItem,0> >::ExecuteIfBound() (0x000007fecea3d456) + 38 bytes [c:\unreal45\unreal\engine\source\runtime\core\public\delegates\delegatesignatureimpl.inl:1072]
UE4Editor-ContentBrowser.dll!SListView<TSharedPtr<FAssetViewItem,0> >::Private_OnItemDoubleClicked() (0x000007feceaccabf) + 41 bytes [c:\unreal45\unreal\engine\source\runtime\slate\public\widgets\views\slistview.h:687]
UE4Editor-ContentBrowser.dll!STableRow<TSharedPtr<FAssetViewItem,0> >::OnMouseButtonDoubleClick() (0x000007feceab804f) + 0 bytes [c:\unreal45\unreal\engine\source\runtime\slate\public\widgets\views\stablerow.h:180]
UE4Editor-Slate.dll!FSlateApplication::ProcessMouseButtonDoubleClickEvent() (0x000007fedb10d705) + 30 bytes [c:\unreal45\unreal\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:3436]
UE4Editor-Slate.dll!FSlateApplication::OnMouseDoubleClick() (0x000007fedb0fb36b) + 19 bytes [c:\unreal45\unreal\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:3413]
UE4Editor-Core.dll!FWindowsApplication::ProcessDeferredMessage() (0x000007fede539aac) + 32 bytes [c:\unreal45\unreal\engine\source\runtime\core\private\windows\windowsapplication.cpp:1288]
UE4Editor-Core.dll!FWindowsApplication::DeferMessage() (0x000007fede5260db) + 74 bytes [c:\unreal45\unreal\engine\source\runtime\core\private\windows\windowsapplication.cpp:1637]
UE4Editor-Core.dll!FWindowsApplication::ProcessMessage() (0x000007fede53adb9) + 41 bytes [c:\unreal45\unreal\engine\source\runtime\core\private\windows\windowsapplication.cpp:737]
UE4Editor-Core.dll!FWindowsApplication::AppWndProc() (0x000007fede522a22) + 0 bytes [c:\unreal45\unreal\engine\source\runtime\core\private\windows\windowsapplication.cpp:599]
USER32.dll!UnknownFunction (0x00000000779d9bd1) + 0 bytes [UnknownFile:0]
USER32.dll!UnknownFunction (0x00000000779d98da) + 0 bytes [UnknownFile:0]
UE4Editor-Core.dll!FWindowsPlatformMisc::PumpMessages() (0x000007fede53b276) + 48 bytes [c:\unreal45\unreal\engine\source\runtime\core\private\windows\windowsplatformmisc.cpp:757]
UE4Editor.exe!FEngineLoop::Tick() (0x000000013fceb082) + 8 bytes [c:\unreal45\unreal\engine\source\runtime\launch\private\launchengineloop.cpp:2111]
UE4Editor.exe!GuardedMain() (0x000000013fce0c3e) + 0 bytes [c:\unreal45\unreal\engine\source\runtime\launch\private\launch.cpp:133]
UE4Editor.exe!GuardedMainWrapper() (0x000000013fce0caa) + 5 bytes [c:\unreal45\unreal\engine\source\runtime\launch\private\windows\launchwindows.cpp:125]
UE4Editor.exe!WinMain() (0x000000013fcec859) + 17 bytes [c:\unreal45\unreal\engine\source\runtime\launch\private\windows\launchwindows.cpp:201]
UE4Editor.exe!__tmainCRTStartup() (0x000000013fced789) + 21 bytes [f:\dd\vctools\crt\crtw32\dllstuff\crtexe.c:618]
kernel32.dll!UnknownFunction (0x00000000778b59ed) + 0 bytes [UnknownFile:0]
ntdll.dll!UnknownFunction (0x0000000077aec541) + 0 bytes [UnknownFile:0]
ntdll.dll!UnknownFunction (0x0000000077aec541) + 0 bytes [UnknownFile:0]

I don’t think I done anything unusual before this started happening, it seemed random but has persisted for a number of weeks.

Does anyone have any idea how I can fix this?

Hey -

In addition to the callstack you provided, it would also help find the cause of this crash if you could get the logs and dump file from the crash as well. The following link mentions in the Editor Session Log section where in your project folder the logs are saved. If you could attach them to the post as well it could help determine what is happening in your project. Here is the link to help find the log files: A new, community-hosted Unreal Engine Wiki - Announcements - Epic Developer Community Forums

Hi ,
Thanks, here is the log and dump file. Let me know if there’s anything else which could help.link text

Hey -

I have entered this crash into our internal tracking system (TTP #349810) for further investigation.

Cheers

This problem is happening to me now too, first with an old BP but now I can’t even make a new one

Just to add, today as a test I deleted the Binaries, DerivedDataCache, Intermediate and Saved folders from the project folder, and rebuilt - widgets now open fine.

1 Like

WHAT??? I am going to go try this now. …

IT WORKED! You glorious fatherfucker!

Not only that but my project folder is now LESS THAN TEN MEGABYTES!

Rebuilt?? How do I rebuild?

Delete the stuff while game is open and then Build All?

Hey, it is only relevant to C++ projects, if you delete those files and try open it, it will ask to rebuild them. It will ask to rebuild if you delete the Binaries folder in a c++ project. So if you don’t delete that, it won’t say anything. You can make any project a C++ project by adding code through File - Add code to project.

Obviously back up your project before doing this. And I’m not sure which folder actually fixed it by being removed. I just deleted them all, but there’s probably only one folder that was responsible.

Maybe someone who knows more about it could add here, which folder is most likely causing the problems.

I’ve been having this issue as well, and for the record I only deleted the “saved” folder to get the editor working again.

It’s from closing either the timeline or animations pane in the widget editor.

STRs:
Open a widget editor window
Close the Animations tab & the Timeline tab
close the editor
reopen the editor
attempt to open any widget editor
observe the crash

Hey -

Thank you for the reproduction steps which I have included with the original report. This bug has been addressed internally and should be fixed in a future update to the engine.

Cheers