Access Violation when starting game

Hey, since some time everytime I start my game, the editor crashes because of an access violation. This happens in every level, even the default one with no additional actors. I recreated the project aso. but nothing helped so far.

Callstack:

UE4Editor-Engine.dll!00007ffde5e42dac() Unknown
UE4Editor-UnrealEd.dll!00007ffde2f1777a() Unknown
UE4Editor-LevelEditor.dll!00007ffddc930d25() Unknown
UE4Editor-LevelEditor.dll!00007ffddc944ff6() Unknown
UE4Editor-LevelEditor.dll!00007ffddc9312be() Unknown
UE4Editor-LevelEditor.dll!00007ffddc96f987() Unknown
UE4Editor-LevelEditor.dll!00007ffddc932a11() Unknown
UE4Editor-LevelEditor.dll!00007ffddc945fb4() Unknown
UE4Editor-SlateCore.dll!00007ffdf6439876() Unknown
UE4Editor-SlateCore.dll!00007ffdf643befc() Unknown
UE4Editor-Slate.dll!00007ffdf774ff60() Unknown
UE4Editor-SlateCore.dll!00007ffdf6496a45() Unknown
UE4Editor-SlateCore.dll!00007ffdf64329a0() Unknown
UE4Editor-SlateCore.dll!00007ffdf643bf7f() Unknown
UE4Editor-Slate.dll!00007ffdf7594d75() Unknown
UE4Editor-SlateCore.dll!00007ffdf6496b38() Unknown
UE4Editor-SlateCore.dll!00007ffdf6432a10() Unknown
UE4Editor-SlateCore.dll!00007ffdf643bff5() Unknown
UE4Editor-Slate.dll!00007ffdf75951c5() Unknown
UE4Editor-SlateCore.dll!00007ffdf6439876() Unknown
UE4Editor-SlateCore.dll!00007ffdf643befc() Unknown
UE4Editor-Slate.dll!00007ffdf758e6d0() Unknown
UE4Editor-SlateCore.dll!00007ffdf643aed0() Unknown
UE4Editor-Slate.dll!00007ffdf75b74c4() Unknown
UE4Editor-Slate.dll!00007ffdf7561920() Unknown
UE4Editor-Slate.dll!00007ffdf7750cda() Unknown
UE4Editor-SlateCore.dll!00007ffdf6439876() Unknown
UE4Editor-SlateCore.dll!00007ffdf643befc() Unknown
UE4Editor-Slate.dll!00007ffdf758e630() Unknown
UE4Editor-SlateCore.dll!00007ffdf643aed0() Unknown
UE4Editor-Slate.dll!00007ffdf75b74c4() Unknown
UE4Editor-Slate.dll!00007ffdf7561920() Unknown
UE4Editor-Slate.dll!00007ffdf7750cda() Unknown
UE4Editor-SlateCore.dll!00007ffdf6439876() Unknown
UE4Editor-SlateCore.dll!00007ffdf643befc() Unknown
UE4Editor-Slate.dll!00007ffdf758e630() Unknown
UE4Editor-SlateCore.dll!00007ffdf643aed0() Unknown
UE4Editor-Slate.dll!00007ffdf75b74c4() Unknown
UE4Editor-Slate.dll!00007ffdf7561920() Unknown
UE4Editor-Slate.dll!00007ffdf7750cda() Unknown
UE4Editor-SlateCore.dll!00007ffdf6439876() Unknown
UE4Editor-SlateCore.dll!00007ffdf643befc() Unknown
UE4Editor-Slate.dll!00007ffdf758e630() Unknown
UE4Editor-SlateCore.dll!00007ffdf643aed0() Unknown
UE4Editor-Slate.dll!00007ffdf75b74c4() Unknown
UE4Editor-Slate.dll!00007ffdf7561920() Unknown
UE4Editor-Slate.dll!00007ffdf7750cda() Unknown
UE4Editor-SlateCore.dll!00007ffdf6496a45() Unknown
UE4Editor-SlateCore.dll!00007ffdf64329a0() Unknown
UE4Editor-SlateCore.dll!00007ffdf643bf7f() Unknown
UE4Editor-Slate.dll!00007ffdf7594d75() Unknown
UE4Editor-SlateCore.dll!00007ffdf6439876() Unknown
UE4Editor-SlateCore.dll!00007ffdf643befc() Unknown
UE4Editor-Slate.dll!00007ffdf758e40f() Unknown
UE4Editor-SlateCore.dll!00007ffdf6496b38() Unknown
UE4Editor-SlateCore.dll!00007ffdf6432a10() Unknown
UE4Editor-SlateCore.dll!00007ffdf643bff5() Unknown
UE4Editor-LevelEditor.dll!00007ffddc849445() Unknown
UE4Editor-SlateCore.dll!00007ffdf6439876() Unknown
UE4Editor-SlateCore.dll!00007ffdf643befc() Unknown
UE4Editor-LevelEditor.dll!00007ffddc945a54() Unknown
UE4Editor-SlateCore.dll!00007ffdf6439876() Unknown
UE4Editor-SlateCore.dll!00007ffdf643befc() Unknown
UE4Editor-Slate.dll!00007ffdf774ff60() Unknown
UE4Editor-SlateCore.dll!00007ffdf6496a45() Unknown
UE4Editor-SlateCore.dll!00007ffdf64329a0() Unknown
UE4Editor-SlateCore.dll!00007ffdf643bf7f() Unknown
UE4Editor-Slate.dll!00007ffdf7594d75() Unknown
UE4Editor-SlateCore.dll!00007ffdf6496b38() Unknown
UE4Editor-SlateCore.dll!00007ffdf6432a10() Unknown
UE4Editor-SlateCore.dll!00007ffdf643bff5() Unknown
UE4Editor-Slate.dll!00007ffdf75951c5() Unknown
UE4Editor-SlateCore.dll!00007ffdf6439876() Unknown
UE4Editor-SlateCore.dll!00007ffdf643befc() Unknown
UE4Editor-Slate.dll!00007ffdf758e6d0() Unknown
UE4Editor-SlateCore.dll!00007ffdf643aed0() Unknown
UE4Editor-Slate.dll!00007ffdf75b74c4() Unknown
UE4Editor-Slate.dll!00007ffdf7561920() Unknown
UE4Editor-Slate.dll!00007ffdf7750cda() Unknown
UE4Editor-SlateCore.dll!00007ffdf6496a45() Unknown
UE4Editor-SlateCore.dll!00007ffdf64329a0() Unknown
UE4Editor-SlateCore.dll!00007ffdf643bf7f() Unknown
UE4Editor-Slate.dll!00007ffdf7594d75() Unknown
UE4Editor-SlateCore.dll!00007ffdf6439876() Unknown
UE4Editor-SlateCore.dll!00007ffdf643befc() Unknown
UE4Editor-Slate.dll!00007ffdf758e40f() Unknown
UE4Editor-SlateCore.dll!00007ffdf6496b38() Unknown
UE4Editor-SlateCore.dll!00007ffdf6432a10() Unknown
UE4Editor-SlateCore.dll!00007ffdf64531b7() Unknown
UE4Editor-SlateCore.dll!00007ffdf6496b38() Unknown
UE4Editor-SlateCore.dll!00007ffdf6432a10() Unknown
UE4Editor-SlateCore.dll!00007ffdf64531b7() Unknown
UE4Editor-SlateCore.dll!00007ffdf6496a45() Unknown
UE4Editor-SlateCore.dll!00007ffdf64329a0() Unknown
UE4Editor-SlateCore.dll!00007ffdf6453065() Unknown
UE4Editor-SlateCore.dll!00007ffdf6439876() Unknown
UE4Editor-SlateCore.dll!00007ffdf643befc() Unknown
UE4Editor-MainFrame.dll!00007ffddc636545() Unknown
UE4Editor-Slate.dll!00007ffdf761c918() Unknown
UE4Editor-Slate.dll!00007ffdf75aa780() Unknown
UE4Editor-Slate.dll!00007ffdf7628e99() Unknown
UE4Editor.exe!00007ff75b8f1e1b() Unknown
UE4Editor.exe!00007ff75b8f5231() Unknown
UE4Editor.exe!00007ff75b9098ca() Unknown
UE4Editor.exe!00007ff75b90b0c6() Unknown
[External Code]

Error Message:

    Exception thrown at 0x00007FFDC8A62DAC (UE4Editor-Engine.dll) in UE4Editor.exe: 0xC0000005: Access        violation reading location 0xFFFFFFFFFFFFFFFF.

I tried everything to solve this, I even completely recreated the project (start new project, create the classes one by one, paste the code) and the error still occurs.