Ok, found it, changed it – thanks!
But of course I have a brand new error.
Ensure condition failed: NewObject->IsA(this->GeneratedClass) [File:C:\SVN_Ark\Engine\Source\Runtime\Engine\Private\Blueprint.cpp] [Line: 585]
Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0x00000040 VERSION: 247.83 UE4Editor-Engine
Yarg.