Summary
The error shown in the log appears to be caused by Unreal Editor for Fortnite failing to launch the Unreal Build Tool (UBT), which prevents the engine from properly validating SDKs and initializing parts of the editor. Multiple pak files and encrypted containers are attempting to mount successfully, but the critical failure occurs when the system cannot execute Build.bat from the Fortnite engine directory, leading to AutoSDK warnings and eventually instability or a crash during startup.
Please select what you are reporting on:
Unreal Editor for Fortnite
What Type of Bug are you experiencing?
Other
Steps to Reproduce
launch UEFN
Expected Result
UEFN Opens, and you enter the desired project.
Observed Result
CRASH, WITH FATAL ERROR
Platform(s)
PC | WINDOWS
Additional Notes
TITLED AS A FATAL ERROR IN THE CRASH REPORT | OPENED A TICKET WITH SUPPORT AND THEY INFORMED ME TO POST IT HERE FOR FURTHER INVESTIGATION | ONLY ERROR LIKE THIS NOTED SO FAR
HAPPENED AFTER THE | 40.40 UPDATE .
HERE ARE THE EDITOR LOGS AND CRASH REPORTS
UnrealEditorFortnite.log (1.8 MB)
UEMinidump.dmp (3.8 MB)
CrashReportClient.ini (260 Bytes)
CrashContext.runtime-xml (192.4 KB)
Fatal error: [File:Z:\UEVFS\Root\Engine\Source\Runtime\D3D12RHI\Private\D3D12Util.cpp] [Line: 1050]
SwapChain1->ResizeBuffers(NumBackBuffers, SizeX, SizeY, UE::DXGIUtilities::GetSwapChainFormat(PixelFormat), SwapChainFlags) failed
at Z:\UEVFS\Root\Engine\Source\Runtime\D3D12RHI\Private\Windows\WindowsD3D12Viewport.cpp:322
with error DXGI_ERROR_INVALID_CALL
Viewport=0x000001F99CD2FC00, Num=3, Size=(1927,1032), PF=18, DXGIFormat=0x18, Fullscreen=0, AllowTearing=1
0x00007ffb913f6623 UnrealEditorFortnite-Engine-Win64-Shipping.dll!UnknownFunction
0x00007ffb9140323f UnrealEditorFortnite-Engine-Win64-Shipping.dll!UnknownFunction
0x00007ffb913ff594 UnrealEditorFortnite-Engine-Win64-Shipping.dll!UnknownFunction
0x00007ffb913fe627 UnrealEditorFortnite-Engine-Win64-Shipping.dll!UnknownFunction
0x00007ffb913fc30f UnrealEditorFortnite-Engine-Win64-Shipping.dll!UnknownFunction
0x00007ffb8a04a48f UnrealEditorFortnite-Engine-Win64-Shipping.dll!UnknownFunction
0x00007ffb8a034d50 UnrealEditorFortnite-Engine-Win64-Shipping.dll!UnknownFunction
0x00007ffb88bf4b96 UnrealEditorFortnite-Engine-Win64-Shipping.dll!UnknownFunction
0x00007ffb88c0778c UnrealEditorFortnite-Engine-Win64-Shipping.dll!UnknownFunction
0x00007ffb88c074c5 UnrealEditorFortnite-Engine-Win64-Shipping.dll!UnknownFunction
0x00007ff6397aa519 UnrealEditorFortnite-Win64-Shipping.exe!UnknownFunction
0x00007ff63979d62c UnrealEditorFortnite-Win64-Shipping.exe!UnknownFunction
0x00007ff63979d6ba UnrealEditorFortnite-Win64-Shipping.exe!UnknownFunction
0x00007ff63979fb4a UnrealEditorFortnite-Win64-Shipping.exe!UnknownFunction
0x00007ff6397ab454 UnrealEditorFortnite-Win64-Shipping.exe!UnknownFunction
0x00007ff6397abf82 UnrealEditorFortnite-Win64-Shipping.exe!UnknownFunction
0x00007ffd0806e957 KERNEL32.DLL!UnknownFunction
TEXT FILE | IF UNABLE TO READ
what happens,
I select uefn, it opens to the select your island menu, any button pressed after that loads to about 70-90% then crashes, and closes.
I have uninstalled, and reinstalled, and verified fortnite / UEFN. Nothing has worked, I contacted epic games support and they could do nothing but tell me post it here for further investigation. The crash has only been started after the 40.40 Update. I have included everything I know about this issue. Its fatal. and Its the first word of the crash log. Its caused my PC to fully crash a couple times from freezeing it, and lagging so hard from whatever is happening. If more info is needed PLEASE let me know, I need to try to get this back up and running asap. thankyou ! ! ! ! !
my biggest fear is that Ive lost all data from a project i was in the midst of submitting to launch this july. I hope I idnt loose the project.
It happens with wall projects, ( including trying to make a new one )