Fatal Error pls help

Hi,

i am a bginner and in my learn and prepare project for the real project i get this code now :

Fatal error: [File:D:\Build++UE4+Release-4.14+Compile\Sync\Engine\Source\Runtime\CoreUObject\Private\Templates\Casts.cpp] [Line: 11]
Cast of LinkerPlaceholderExportObject /Game/ThirdPersonBP/Blueprints/BP_FloorTileTest1.BP_FloorTileTest1_C:NODE_AddChildActorComponent-2.NODE_AddChildActorComponent-2_BP_PIckUp_C_CAT to Actor failed

I have never coded in c++ and ue4.

I dont know what i did but normally i would just remove the the last things what i did to this project and all would be fine. My problem is i cant even start now the project with this error so i cant remove it also what i did.

Also dotn know how to access ue4 via c++.
My simple idea was just open the source code find the last added things and remove them.
But that works only with pure coding and i dotn knwo how it works with this engine.

I cant work on if i cant start this project and that costs me easy 2-3 weeks to rebuilt all even there is almost noting in it.

You have a Cast node in: BP_FloorTileTest1

This node is failing to cast to a BP_PIckUp.

Look at the FloorTileTest1 Blueprint and look for that cast.

My problem is i cant even start my project from the bibliothek engine.

So i cant do anything.

In bibliothek when i click on my project runv1 this fatal error occurs and shut down after.

Does it work to create a new blank project, copy the faulty blueprint to the new project, fix it and copy it back?
And you should really do yourself a favour and start using a version control system like git or svn.

You can try finding the BP_FloorTileTest1.asset and moving it out of the content folder.

Then, launch the editor, move the BP_FloorTileTest1.asset file back into the directory it was in prior to launch, then open the blueprint and try to fix it there.

Thanks a lot.

That worked. I opened the project folder removed the failed blueprint started the engine and copied the failed blueprint back to the content folder so i have access to it and can remove all fails now.

Problem solved.