Unhandled Exception: EXCEPTION_ACCESS_VIOLATION... Anyone can help with this?

so ive been working on a sword mod and all has been going perfect until i tryed to change the swing animation then i started getting that error everytime tried to equip the item i then changed all the values back to default and i still get that error no matter what anyone know what this may mean or have any insight on how to fix it?

this is the full error:

Fatal error!

Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0x00000040

UE4Editor-Engine.dll!UnknownFunction (0x000007fedf646875) + 0 bytes [UnknownFile:0]
UE4Editor-Engine.dll!UnknownFunction (0x000007fedf6467e9) + 0 bytes [UnknownFile:0]
UE4Editor-ShooterGame.dll!AShooterWeapon::PlayWeaponAnimation() (0x000007fed5d03ae8) + 0 bytes [f:\ue4\unrealengine\projects\shootergame\source\shootergame\private\shooterweapon.cpp:1279]
UE4Editor-ShooterGame.dll!AShooterWeapon::OnEquip() (0x000007fed5d03237) + 0 bytes [f:\ue4\unrealengine\projects\shootergame\source\shootergame\private\shooterweapon.cpp:323]
UE4Editor-ShooterGame.dll!AShooterCharacter::SetCurrentWeapon() (0x000007fed5c36abb) + 0 bytes [f:\ue4\unrealengine\projects\shootergame\source\shootergame\private\shootercharacter.cpp:1337]
UE4Editor-ShooterGame.dll!AShooterCharacter::GivePrimalItemWeapon() (0x000007fed5c2e8ee) + 14 bytes [f:\ue4\unrealengine\projects\shootergame\source\shootergame\private\shootercharacter.cpp:1023]
UE4Editor-Engine.dll!UnknownFunction (0x000007fedf42c37c) + 0 bytes [UnknownFile:0]
UE4Editor-Engine.dll!UnknownFunction (0x000007fedf476555) + 0 bytes [UnknownFile:0]
UE4Editor-Engine.dll!UnknownFunction (0x000007fedf0c74e6) + 0 bytes [UnknownFile:0]
UE4Editor-UnrealEd.dll!UnknownFunction (0x000007feda9d1192) + 0 bytes [UnknownFile:0]
UE4Editor-UnrealEd.dll!UnknownFunction (0x000007fedae35076) + 0 bytes [UnknownFile:0]
UE4Editor.exe!UnknownFunction (0x000000013fd993e4) + 0 bytes [UnknownFile:0]
UE4Editor.exe!UnknownFunction (0x000000013fd8ed0f) + 0 bytes [UnknownFile:0]
UE4Editor.exe!UnknownFunction (0x000000013fd8ed7a) + 0 bytes [UnknownFile:0]
UE4Editor.exe!UnknownFunction (0x000000013fd9aa60) + 0 bytes [UnknownFile:0]
UE4Editor.exe!UnknownFunction (0x000000013fd9b999) + 0 bytes [UnknownFile:0]
kernel32.dll!UnknownFunction (0x0000000076e3652d) + 0 bytes [UnknownFile:0]
ntdll.dll!UnknownFunction (0x000000007706c521) + 0 bytes [UnknownFile:0]
ntdll.dll!UnknownFunction (0x000000007706c521) + 0 bytes [UnknownFile:0]