Unreal Editor Crashing when open project without External / Dual monitor connected

I am having an issue with a project I created while my laptop was connected to a smart TV (Veon tv).

I have been working on this project for some time now. Due to covid lockdown I have not disconnected my laptop from dual monitor for a while and tried to open my project while my laptop is not connected to any external monitors, the editor crashes as soon as mouse cursor leaves viewport.

Laptop details:
-Device Name: LAPTOP-AC108NU2
-Processor: AMD Ryzen 5, 3550h with Radeon Vega Mobile GFX 2.10 GHz
-RAM: 16gb
-System type: 64 bit

TV Monitor Details:
(will add specific details soon)

Things I found while trouble shooting:

-If laptop is not connected to external monitor the editor crashes when project opens unless mouse is inside viewport, but will crash as soon as mouse leaves viewport.

-If laptop is connected to external monitor and the external monitor is set as main display in settings everything works fine as unreal will open on external monitor.

-If I have Unreal editor is open and I go into settings and set my laptop screen as main display Unreal will crash.

-If I have Unreal open and disconnect the HDMI cable it will crash.

-If I drag editor from external monitor to laptop screen Unreal will crash

-If I open projects that I created while laptop is not connected to external display.

-If I open projects that I created while my laptop is not connected to any external monitors they work completely fine regardless to whether my laptop is connected to external monitor or not and I can drag editor back and forth between displays without problems

EDIT: Found something new! -If I have the display settings (size of text, apps, and other items) set to the same percentages instead of the recommended settings (which is 150% for tv monitor and 125% for laptop) the unreal editor will not crash unless I maximize the window.

End of Crash log file:

[2021.02.01-21.15.57:297] 1]LogCollectionManager: Fixed up redirectors for 0 collections in 0.000017 seconds (updated 0 objects)
[2021.02.01-21.16.01:173] 2]LogShaderCompilers: Display: Worker (3/5): shaders left to compile 6472
[2021.02.01-21.16.01:908] 2]LogShaderCompilers: Display: Worker (2/5): shaders left to compile 6462
[2021.02.01-21.16.02:585] 2]LogThreadingWindows: Error: Runnable thread RHIThread crashed.
[2021.02.01-21.16.02:585] 2]LogWindows: Error: === Critical error: ===
[2021.02.01-21.16.02:585] 2]LogWindows: Error:
[2021.02.01-21.16.02:586] 2]LogWindows: Error: Fatal error!
[2021.02.01-21.16.02:586] 2]LogWindows: Error:
[2021.02.01-21.16.02:586] 2]LogWindows: Error: Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0x0000000000000048
[2021.02.01-21.16.02:586] 2]LogWindows: Error:
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff87906a790 nvwgf2umx.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff87903a34b nvwgf2umx.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff878ccc1da nvwgf2umx.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff878ccbd7b nvwgf2umx.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff878284d4a nvwgf2umx.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff878e12d5c nvwgf2umx.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff878ce61f8 nvwgf2umx.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff878fbe29a nvwgf2umx.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff878fbc492 nvwgf2umx.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff878363121 nvwgf2umx.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff8784da579 nvwgf2umx.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff87832a753 nvwgf2umx.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff87ca1bf66 d3d12.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff87ca1b483 d3d12.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff8c02674a9 dxgi.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff8c026983b dxgi.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff8c022a3ac dxgi.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff8c01f4b6a dxgi.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff8c02048f9 dxgi.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff8c020373b dxgi.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff8c01f5050 dxgi.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff83115e74a UE4Editor-D3D12RHI.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff83115e1da UE4Editor-D3D12RHI.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff831165ccd UE4Editor-D3D12RHI.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff848e82f0c UE4Editor-RHI.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff848e87b73 UE4Editor-RHI.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff848e710eb UE4Editor-RHI.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff848e89ad0 UE4Editor-RHI.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff845d1ed11 UE4Editor-Core.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff845d1f0fe UE4Editor-Core.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff84b1a2a73 UE4Editor-RenderCore.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff846277cdb UE4Editor-Core.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff846270970 UE4Editor-Core.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff8c2a07034 KERNEL32.DLL!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error: [Callstack] 0x00007ff8c47fd0d1 ntdll.dll!UnknownFunction ]
[2021.02.01-21.16.02:586] 2]LogWindows: Error:
[2021.02.01-21.16.02:586] 2]LogWindows: Error: Crash in runnable thread RHIThread
[2021.02.01-21.16.02:603] 2]LogExit: Executing StaticShutdownAfterError
[2021.02.01-21.16.02:603] 2]LogWindows: FPlatformMisc::RequestExit(1)
[2021.02.01-21.16.02:603] 2]LogCore: Engine exit requested (reason: Win RequestExit)
[2021.02.01-21.16.02:615] 2]Log file closed, 02/02/21 10:16:02

Launcher Crash Report:

Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0x0000000000000048


I fixed it! I opened up the the ini files in the config folder and compared them to the ini files of my older project that was not having this problem.

In DefaultEngine.ini I found this -



This does not exist in the ini file of my working project and it says RHI-Thread in the error log so I removed it and now everything is working like normal.

I still have no idea what this means though and if anyone has any info it would be much appreciated.

GrimStarGames, I am having the same problem, can you please go over exactly what you did so I can may fix it, it would mean a lot!

Hi, sorry for late reply.

I opened a project that was not crashing to make sure it did not experience the same issue. Then I opened the the Config folders for that project and the one that is crashing (this folder can be found in file explorer outside the engine).

The config folder contains .ini files.

I went through each ini file from both projects and compared them, which is how I found the line “DefaultGraphicsRHI=DefaultGraphicsRHI_DX12” in the ini file of the project that is crashing but does not exist in the ini file of the one that is not crashing.

As you can see in the error log from the crashing project, it says “Error: Crash in runnable thread RHIThread” which looks similar to the line in the the ini file.

So I deleted this section from the ini file and everything works fine now.

Note: Be care full with playing with ini files and defintly make a back up before changing anything.