Assertion failed: Index.IsExport() && ExportMap.IsValidIndex(Index.ToExport()) [File:D:\build\++UE5\Sync\Engine\Source\Runtime\CoreUObject\Public\UObject\Linker.h] [

Development Platform & Builds
, ,
1

any help with this on trying to open a project

Assertion failed: Index.IsExport() && ExportMap.IsValidIndex(Index.ToExport()) [File:D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Public\UObject\Linker.h] [Line: 165]

UnrealEditor_CoreUObject!FLinkerLoad::FixupImportMap() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:1932]
UnrealEditor_CoreUObject!FLinkerLoad::ProcessPackageSummary() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:812]
UnrealEditor_CoreUObject!FLinkerLoad::Tick() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:932]
UnrealEditor_CoreUObject!FLinkerLoad::CreateLinker() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:550]
UnrealEditor_CoreUObject!GetPackageLinker() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\Linker.cpp:875]
UnrealEditor_CoreUObject!LoadPackageInternal() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\UObjectGlobals.cpp:1718]
UnrealEditor_CoreUObject!FLinkerLoad::VerifyImportInner'::2’::<lambda_1>::operator()() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:3394]
UnrealEditor_CoreUObject!FLinkerLoad::VerifyImportInner() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:3529]
UnrealEditor_CoreUObject!FLinkerLoad::VerifyImport() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:3037]
UnrealEditor_CoreUObject!FLinkerLoad::VerifyImportInner() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:3558]
UnrealEditor_CoreUObject!FLinkerLoad::VerifyImport() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:3037]
UnrealEditor_CoreUObject!FLinkerLoad::Verify() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:2815]
UnrealEditor_CoreUObject!FLinkerLoad::FinalizeCreation() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:2617]
UnrealEditor_CoreUObject!FLinkerLoad::ProcessPackageSummary() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:882]
UnrealEditor_CoreUObject!FLinkerLoad::Tick() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:932]
UnrealEditor_CoreUObject!FLinkerLoad::CreateLinker() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:550]
UnrealEditor_CoreUObject!GetPackageLinker() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\Linker.cpp:875]
UnrealEditor_CoreUObject!LoadPackageInternal() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\UObjectGlobals.cpp:1718]
UnrealEditor_CoreUObject!FLinkerLoad::VerifyImportInner'::2’::<lambda_1>::operator()() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:3394]
UnrealEditor_CoreUObject!FLinkerLoad::VerifyImportInner() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:3529]
UnrealEditor_CoreUObject!FLinkerLoad::VerifyImport() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:3037]
UnrealEditor_CoreUObject!FLinkerLoad::VerifyImportInner() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:3558]
UnrealEditor_CoreUObject!FLinkerLoad::VerifyImport() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:3037]
UnrealEditor_CoreUObject!FLinkerLoad::Verify() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:2815]
UnrealEditor_CoreUObject!FLinkerLoad::FinalizeCreation() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:2617]
UnrealEditor_CoreUObject!FLinkerLoad::ProcessPackageSummary() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:882]
UnrealEditor_CoreUObject!FLinkerLoad::Tick() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:932]
UnrealEditor_CoreUObject!FLinkerLoad::CreateLinker() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\LinkerLoad.cpp:550]
UnrealEditor_CoreUObject!GetPackageLinker() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\Linker.cpp:875]
UnrealEditor_CoreUObject!LoadPackageInternal() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\UObjectGlobals.cpp:1718]
UnrealEditor_CoreUObject!LoadPackage() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\UObjectGlobals.cpp:2014]
UnrealEditor_CoreUObject!LoadPackage() [D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\UObjectGlobals.cpp:1987]
UnrealEditor_UnrealEd!UEditorEngine::Map_Load() [D:\build++UE5\Sync\Engine\Source\Editor\UnrealEd\Private\EditorServer.cpp:2708]
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_UnrealEd!FEditorFileUtils::LoadDefaultMapAtStartup() [D:\build++UE5\Sync\Engine\Source\Editor\UnrealEd\Private\FileHelpers.cpp:4946]
UnrealEditor_UnrealEd!FUnrealEdMisc::OnInit() [D:\build++UE5\Sync\Engine\Source\Editor\UnrealEd\Private\UnrealEdMisc.cpp:371]
UnrealEditor_UnrealEd!EditorInit() [D:\build++UE5\Sync\Engine\Source\Editor\UnrealEd\Private\UnrealEdGlobals.cpp:135]
UnrealEditor!GuardedMain() [D:\build++UE5\Sync\Engine\Source\Runtime\Launch\Private\Launch.cpp:162]
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

2

I was running into the same assert when trying to launch my game from Rider/Visual Studio directly, rather than via the editor.

In order to launch it from Rider/Visual Studio after making C++ changes, I had to cook the build. Various assets seemed to be stale without doing that.