Hi, on the start up editor when it hits 80%, this line triggered the break point which I couldn’t understand what is the cause. the recent actions I’ve done is disable Intellisense error warning and Rebuild the project, then this problem started kicking into my build at the Casts.cpp UE_LOG line. The reason I want to disable Intellisense error is due to the DECLARE_LOG_CATEGORY_EXTERN keep throwing declaration error (something like incompatible with my log name in my other actor class). I’ve also tried enable back and rebuild the project but no luck.
So is there any solution? Right now I have to rush on school final year project and this problem came up need help urgent 
Thanks.
Update: Here is the crash report
MachineId:3C1C6E3D492F2358AFCFE78B8D94E644
Unknown exception - code 00000001 (first/second chance not available)
Fatal error: [File:D:\GitHub\UnrealEngine\Engine\Source\Runtime\CoreUObject\Private\Templates\Casts.cpp] [Line: 11]
Cast of RGBCharacter //Script//RGB.Default__RGBCharacter to Level failed
KERNELBASE + 35740 bytes
UE4Editor_Core!FOutputDeviceWindowsError::Serialize() + 292 bytes [d:\github\unrealengine\engine\source\runtime\core\private\windows\windowsplatformoutputdevices.cpp:95]
UE4Editor_Core!FMsg::Logf__VA() + 463 bytes [d:\github\unrealengine\engine\source\runtime\core\private\misc\outputdevice.cpp:531]
UE4Editor_CoreUObject!CastLogError() + 115 bytes [d:\github\unrealengine\engine\source\runtime\coreuobject\private\templates\casts.cpp:12]
UE4Editor_Engine!CastChecked<ULevel,UObject>() + 172 bytes [d:\github\unrealengine\engine\source\runtime\coreuobject\public\templates\casts.h:154]
UE4Editor_Engine!TActorIteratorBase<FActorFilter,FTickableLevelFilter>::operator++() + 255 bytes [d:\github\unrealengine\engine\source\runtime\engine\public\engineutils.h:352]
UE4Editor_Engine!UWorld::UpdateCullDistanceVolumes() + 1249 bytes [d:\github\unrealengine\engine\source\runtime\engine\private\world.cpp:1237]
UE4Editor_Engine!UWorld::InitializeNewWorld() + 796 bytes [d:\github\unrealengine\engine\source\runtime\engine\private\world.cpp:987]
UE4Editor_Engine!UWorld::CreateWorld() + 561 bytes [d:\github\unrealengine\engine\source\runtime\engine\private\world.cpp:1053]
UE4Editor_Engine!UEngine::Init() + 1842 bytes [d:\github\unrealengine\engine\source\runtime\engine\private\unrealengine.cpp:750]
UE4Editor_UnrealEd!UEditorEngine::InitEditor() + 46 bytes [d:\github\unrealengine\engine\source\editor\unrealed\private\editor.cpp:447]
UE4Editor_UnrealEd!UEditorEngine::Init() + 1437 bytes [d:\github\unrealengine\engine\source\editor\unrealed\private\editor.cpp:602]
UE4Editor_UnrealEd!UUnrealEdEngine::Init() + 45 bytes [d:\github\unrealengine\engine\source\editor\unrealed\private\unrealedengine.cpp:42]
UE4Editor!FEngineLoop::Init() + 1246 bytes [d:\github\unrealengine\engine\source\runtime\launch\private\launchengineloop.cpp:1967]
UE4Editor_UnrealEd!EditorInit() + 920 bytes [d:\github\unrealengine\engine\source\editor\unrealed\private\unrealed.cpp:63]
UE4Editor!GuardedMain() + 925 bytes [d:\github\unrealengine\engine\source\runtime\launch\private\launch.cpp:133]
UE4Editor!GuardedMainWrapper() + 26 bytes [d:\github\unrealengine\engine\source\runtime\launch\private\windows\launchwindows.cpp:126]
UE4Editor!WinMain() + 249 bytes [d:\github\unrealengine\engine\source\runtime\launch\private\windows\launchwindows.cpp:202]
UE4Editor!__tmainCRTStartup() + 329 bytes [f:\dd\vctools\crt\crtw32\dllstuff\crtexe.c:618]