URGENT! I can't open my second Level in the Editor anymore! (Fatal error)

Here’s what’s going on. I’m in the “Light” part of my game. After waiting a long time for my lights to be built, I launched my game, and few seconds later UE4 crashed. I didn’t save my project after my Light Build. Therefore I forced UE4 to close, then restarted it and found myself in the level I was on before the first crash, with my Lights not built. But when I try to open another level (A Menu Level) in the Editor (another Map), UE4 crashes. I tried several times, but this didn’t help me. Maybe a light rebuild is the solution, as the last time it crashed ?

Here’s the crash report:

Fatal error: [File:D:/Build/++UE4/Sync/Engine/Source/Editor/UnrealEd/Private/EditorServer.cpp] [Line: 1992] World Memory Leaks: 2 leaks objects and packages. See The output above.

UE4Editor_UnrealEd
UE4Editor_UnrealEd
UE4Editor_UnrealEd
UE4Editor_UnrealEd
UE4Editor_UnrealEd
UE4Editor_UnrealEd
UE4Editor_UnrealEd
UE4Editor_AssetTools
UE4Editor_UnrealEd
UE4Editor_ContentBrowser
UE4Editor_ContentBrowser
UE4Editor_ContentBrowser
UE4Editor_ContentBrowser
UE4Editor_ContentBrowser
UE4Editor_ContentBrowser
UE4Editor_ContentBrowser
UE4Editor_Slate
UE4Editor_Slate
UE4Editor_Slate
UE4Editor_Slate
UE4Editor_ApplicationCore
UE4Editor_ApplicationCore
UE4Editor_ApplicationCore
UE4Editor_ApplicationCore
user32
user32
UE4Editor_ApplicationCore
UE4Editor
UE4Editor
UE4Editor
UE4Editor
UE4Editor
kernel32
ntdll

Sorry to bump this old thread but did you find a fix for this?
I have the exact same issue in UE5, loads the startup map no issues, however, the moment I try to load another level (any) it crashes:

Fatal error: [File:D:\build++UE5\Sync\Engine\Source\Editor\UnrealEd\Private\EditorServer.cpp] [Line: 2043] World Memory Leaks: 2 leaks objects and packages. See The output above.

UnrealEditor_UnrealEd
UnrealEditor_UnrealEd
UnrealEditor_UnrealEd
UnrealEditor_UnrealEd
UnrealEditor_UnrealEd
UnrealEditor_UnrealEd
UnrealEditor_UnrealEd
UnrealEditor_AssetTools
UnrealEditor_UnrealEd
UnrealEditor_UnrealEd
UnrealEditor_UnrealEd
UnrealEditor_ContentBrowserAssetDataSource
UnrealEditor_ContentBrowserAssetDataSource
UnrealEditor_ContentBrowserAssetDataSource
UnrealEditor_ContentBrowser
UnrealEditor_ContentBrowser
UnrealEditor_ContentBrowser
UnrealEditor_ContentBrowser
UnrealEditor_ContentBrowser
UnrealEditor_ContentBrowser
UnrealEditor_ContentBrowser
UnrealEditor_Slate
UnrealEditor_Slate
UnrealEditor_Slate
UnrealEditor_Slate
UnrealEditor_ApplicationCore
UnrealEditor_ApplicationCore
UnrealEditor_ApplicationCore
UnrealEditor_ApplicationCore
user32
user32
UnrealEditor_ApplicationCore
UnrealEditor
UnrealEditor
UnrealEditor
UnrealEditor
UnrealEditor
UnrealEditor
kernel32
ntdll

Edit
The only workaround I have found to this for the time being, was setting the map I wanted as the editor startup map in the project settings and then reopening the project…
(This needed to be done for every level that I wanted to switch to)

Having the same issue. there seems to be a missing file but I have no idea how to figure out which one.

Hi! Same problem here. It allows me to open the project but if I try to open another level, the editor crashes. Sometimes it lets me open one level after the project opens, but just one.

I found these two pages about memory leaks, which may be useful. I temporarily changed my startup level to a more “clean” one, and if I only change between “clean” levels, so far is not crashing.

Fatal error: [File:D:\build\++UE5\Sync\Engine\Source\Editor\UnrealEd\Private\EditorServer.cpp] [Line: 2043] World Memory Leaks: 2 leaks objects and packages. See The output above.

UnrealEditor_UnrealEd!UEditorEngine::CheckForWorldGCLeaks() [D:\build\++UE5\Sync\Engine\Source\Editor\UnrealEd\Private\EditorServer.cpp:2045]
UnrealEditor_UnrealEd!UEditorEngine::EditorDestroyWorld() [D:\build\++UE5\Sync\Engine\Source\Editor\UnrealEd\Private\EditorServer.cpp:2178]
UnrealEditor_UnrealEd!UEditorEngine::Map_Load() [D:\build\++UE5\Sync\Engine\Source\Editor\UnrealEd\Private\EditorServer.cpp:2565]
UnrealEditor_UnrealEd!UEditorEngine::HandleMapCommand() [D:\build\++UE5\Sync\Engine\Source\Editor\UnrealEd\Private\EditorServer.cpp:6291]
UnrealEditor_UnrealEd!UEditorEngine::Exec_Editor() [D:\build\++UE5\Sync\Engine\Source\Editor\UnrealEd\Private\EditorServer.cpp:5752]
UnrealEditor_Core!FExec::Exec() [D:\build\++UE5\Sync\Engine\Source\Runtime\Core\Private\Misc\Exec.cpp:18]
UnrealEditor_Engine!UEngine::Exec() [D:\build\++UE5\Sync\Engine\Source\Runtime\Engine\Private\UnrealEngine.cpp:4686]
UnrealEditor_UnrealEd!UUnrealEdEngine::Exec() [D:\build\++UE5\Sync\Engine\Source\Editor\UnrealEd\Private\UnrealEdSrv.cpp:662]
UnrealEditor_UnrealEd!FEditorFileUtils::LoadMap() [D:\build\++UE5\Sync\Engine\Source\Editor\UnrealEd\Private\FileHelpers.cpp:2908]
UnrealEditor_EngineAssetDefinitions!UAssetDefinition_World::OpenAssets() [D:\build\++UE5\Sync\Engine\Plugins\Editor\EngineAssetDefinitions\Source\Private\AssetDefinition_World.cpp:62]
UnrealEditor_AssetTools!FAssetDefinitionProxy::OpenAssetEditor() [D:\build\++UE5\Sync\Engine\Source\Developer\AssetTools\Private\AssetTools.cpp:244]
UnrealEditor_UnrealEd!UAssetEditorSubsystem::OpenEditorForAsset() [D:\build\++UE5\Sync\Engine\Source\Editor\UnrealEd\Private\Subsystems\AssetEditorSubsystem.cpp:579]
UnrealEditor_UnrealEd!UAssetEditorSubsystem::OpenEditorForAssets_Advanced() [D:\build\++UE5\Sync\Engine\Source\Editor\UnrealEd\Private\Subsystems\AssetEditorSubsystem.cpp:645]
UnrealEditor_UnrealEd!UAssetEditorSubsystem::OpenEditorForAssets() [D:\build\++UE5\Sync\Engine\Source\Editor\UnrealEd\Private\Subsystems\AssetEditorSubsystem.cpp:761]
UnrealEditor_ContentBrowserAssetDataSource!ContentBrowserAssetData::EditOrPreviewAssetFileItems() [D:\build\++UE5\Sync\Engine\Plugins\Editor\ContentBrowser\ContentBrowserAssetDataSource\Source\ContentBrowserAssetDataSource\Private\ContentBrowserAssetDataCore.cpp:372]
UnrealEditor_ContentBrowserAssetDataSource!ContentBrowserAssetData::EditOrPreviewItems() [D:\build\++UE5\Sync\Engine\Plugins\Editor\ContentBrowser\ContentBrowserAssetDataSource\Source\ContentBrowserAssetDataSource\Private\ContentBrowserAssetDataCore.cpp:417]
UnrealEditor_ContentBrowserAssetDataSource!UContentBrowserAssetDataSource::BulkEditItems() [D:\build\++UE5\Sync\Engine\Plugins\Editor\ContentBrowser\ContentBrowserAssetDataSource\Source\ContentBrowserAssetDataSource\Private\ContentBrowserAssetDataSource.cpp:2200]
UnrealEditor_ContentBrowser!SContentBrowser::OnItemsActivated() [D:\build\++UE5\Sync\Engine\Source\Editor\ContentBrowser\Private\SContentBrowser.cpp:3141]
UnrealEditor_ContentBrowser!TBaseSPMethodDelegateInstance<0,SContentBrowser,1,void __cdecl(TArrayView<FContentBrowserItem const ,int>,enum EAssetTypeActivationMethod::Type),FDefaultDelegateUserPolicy>::Execute() [D:\build\++UE5\Sync\Engine\Source\Runtime\Core\Public\Delegates\DelegateInstancesImpl.h:281]
UnrealEditor_ContentBrowser!SAssetView::OnListMouseButtonDoubleClick() [D:\build\++UE5\Sync\Engine\Source\Editor\ContentBrowser\Private\SAssetView.cpp:4081]
UnrealEditor_ContentBrowser!TBaseSPMethodDelegateInstance<0,SAssetView,1,void __cdecl(TSharedPtr<FAssetViewItem,1>),FDefaultDelegateUserPolicy>::ExecuteIfSafe() [D:\build\++UE5\Sync\Engine\Source\Runtime\Core\Public\Delegates\DelegateInstancesImpl.h:298]
UnrealEditor_ContentBrowser!TDelegate<void __cdecl(TSharedPtr<FAssetViewItem,1>),FDefaultDelegateUserPolicy>::ExecuteIfBound<void,0>() [D:\build\++UE5\Sync\Engine\Source\Runtime\Core\Public\Delegates\DelegateSignatureImpl.inl:570]
UnrealEditor_ContentBrowser!SListView<TSharedPtr<FAssetViewItem,1> >::Private_OnItemDoubleClicked() [D:\build\++UE5\Sync\Engine\Source\Runtime\Slate\Public\Widgets\Views\SListView.h:1122]
UnrealEditor_ContentBrowser!STableRow<TSharedPtr<FAssetViewItem,1> >::OnMouseButtonDoubleClick() [D:\build\++UE5\Sync\Engine\Source\Runtime\Slate\Public\Widgets\Views\STableRow.h:423]
UnrealEditor_Slate!FEventRouter::Route<FReply,FEventRouter::FBubblePolicy,FPointerEvent,`FSlateApplication::RoutePointerDoubleClickEvent'::`2'::<lambda_1> >() [D:\build\++UE5\Sync\Engine\Source\Runtime\Slate\Private\Framework\Application\SlateApplication.cpp:442]
UnrealEditor_Slate!FSlateApplication::RoutePointerDoubleClickEvent() [D:\build\++UE5\Sync\Engine\Source\Runtime\Slate\Private\Framework\Application\SlateApplication.cpp:5700]
UnrealEditor_Slate!FSlateApplication::ProcessMouseButtonDoubleClickEvent() [D:\build\++UE5\Sync\Engine\Source\Runtime\Slate\Private\Framework\Application\SlateApplication.cpp:5685]
UnrealEditor_Slate!FSlateApplication::OnMouseDoubleClick() [D:\build\++UE5\Sync\Engine\Source\Runtime\Slate\Private\Framework\Application\SlateApplication.cpp:5648]
UnrealEditor_ApplicationCore!FWindowsApplication::ProcessDeferredMessage() [D:\build\++UE5\Sync\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsApplication.cpp:2235]
UnrealEditor_ApplicationCore!FWindowsApplication::DeferMessage() [D:\build\++UE5\Sync\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsApplication.cpp:2738]
UnrealEditor_ApplicationCore!FWindowsApplication::ProcessMessage() [D:\build\++UE5\Sync\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsApplication.cpp:1099]
UnrealEditor_ApplicationCore!FWindowsApplication::AppWndProc() [D:\build\++UE5\Sync\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsApplication.cpp:937]
user32
user32
UnrealEditor_ApplicationCore!FWindowsPlatformApplicationMisc::PumpMessages() [D:\build\++UE5\Sync\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsPlatformApplicationMisc.cpp:148]
UnrealEditor!FEngineLoop::Tick() [D:\build\++UE5\Sync\Engine\Source\Runtime\Launch\Private\LaunchEngineLoop.cpp:5749]
UnrealEditor!GuardedMain() [D:\build\++UE5\Sync\Engine\Source\Runtime\Launch\Private\Launch.cpp:188]
UnrealEditor!GuardedMainWrapper() [D:\build\++UE5\Sync\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:118]
UnrealEditor!LaunchWindowsStartup() [D:\build\++UE5\Sync\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:258]
UnrealEditor!WinMain() [D:\build\++UE5\Sync\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:298]
UnrealEditor!__scrt_common_main_seh() [D:\a\_work\1\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288]
kernel32
ntdll