Engine crash then my project won't open again

My engine crashed and I can’t open my project. I can open other projects but not this one.
Crash report

Fatal error: [File:D:/Build/++UE4/Sync/Engine/Source/Runtime/CoreUObject/Private/Templates/Casts.cpp] [Line: 10] 
Cast of LinkerPlaceholderExportObject /Game/Blueprints/Waypoints/BP_TextboxWidget.PLACEHOLDER-INST_of_PLACEHOLDER-CLASS__WidgetBlueprint_1 to Blueprint failed


0x00007ffd207d3b29 KERNELBASE.dll!UnknownFunction []
0x00007ffcc3be0216 UE4Editor-Core.dll!UnknownFunction []
0x00007ffcc3be4218 UE4Editor-Core.dll!UnknownFunction []
0x00007ffcc390242d UE4Editor-Core.dll!UnknownFunction []
0x00007ffcbfbf295a UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcb82cef90 UE4Editor-BlueprintGraph.dll!UnknownFunction []
0x00007ffcb82e5f60 UE4Editor-BlueprintGraph.dll!UnknownFunction []
0x00007ffcb821bb6e UE4Editor-BlueprintGraph.dll!UnknownFunction []
0x00007ffcb81c2bc7 UE4Editor-BlueprintGraph.dll!UnknownFunction []
0x00007ffcbe191f4d UE4Editor-UnrealEd.dll!UnknownFunction []
0x00007ffcbb7e4fed UE4Editor-Kismet.dll!UnknownFunction []
0x00007ffcbb7e2be3 UE4Editor-Kismet.dll!UnknownFunction []
0x00007ffcbfb2cc30 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfdb25c1 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfdd691a UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfdb10ba UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfdb2b1b UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfdd8bbc UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfeecd66 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfda790d UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe052d2 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe038c7 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe0539d UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe038c7 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe036e1 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfdbe399 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe0026a UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfdb417e UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfc7a067 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfeeca33 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfda790d UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe052d2 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe038c7 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe0539d UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe038c7 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe036e1 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfdbe399 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe0026a UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfdb417e UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfc7a067 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfeeca33 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfda790d UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe052d2 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe038c7 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe0539d UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe038c7 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe036e1 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfdbe399 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe0026a UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfdb417e UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfc7a067 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfeeca33 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfeebbc0 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbff01e1f UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbff149f5 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbff14088 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe2ecb6 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe42075 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe3df5e UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe3de0f UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe3cef3 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfaf6368 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe3bdf7 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfc0f535 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfe85d32 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfaf6368 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfddae0f UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfef16a7 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfec6478 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfbf61dd UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbff18faf UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ffcbfef5411 UE4Editor-CoreUObject.dll!UnknownFunction []
0x00007ff7e2688179 UE4Editor.exe!UnknownFunction []
0x00007ff7e2680d2c UE4Editor.exe!UnknownFunction []
0x00007ff7e26810ba UE4Editor.exe!UnknownFunction []
0x00007ff7e26840dd UE4Editor.exe!UnknownFunction []
0x00007ff7e2695984 UE4Editor.exe!UnknownFunction []
0x00007ff7e269853a UE4Editor.exe!UnknownFunction []
0x00007ffd22427c24 KERNEL32.DLL!UnknownFunction []
0x00007ffd2358d4d1 ntdll.dll!UnknownFunction []

Try to duplicate the project. Copy and paste anywhere. Then in this duplicate delete everything except Config, Content, .Uproject file. Go to Content/Blueprints/Waypoints and delete the BP_Textwidget. Try again. If this works, go into the old project, Saved, Autosave and copy one of the old saves of BP_Textwidget to your duplicate into the original destination Content/Blueprints/Waypoints

Thank you for your anwser! I thankfully managed to open the project only by deleting two asset files (BP_Textwidget and an HUD asset).

I have working backups but when I try to migrate these assets from them, the project won’t open. These backups were made and opened before the crash happened.

How do you try to migrate? Via copy/paste or via the Migrate function inside the project? Maybe there are dependencies which have to be migrated too.

Via the migrate function (there were no other dependencies for those) but anyways there other issues unfortunately (like other blueprint child components missing). I then did exactly what you said and I could reimport with copy/paste those 2 assets and have them working.

unfortunately my lighting was rebuilt and that meshed up quite some things :confused:

What do you mean? Can you show a comparison?