Unreal Engine Failing to Launch


I was working with UE for the first time in a while this weekend and today it’s failing to launch. The error I get is as follows:


Unknown exception - code c06d007e (first/second chance not available)


KERNELBASE + 24684 bytes
UE4Editor_Engine + 23178089 bytes
UE4Editor_Engine + 21358229 bytes
UE4Editor_Engine + 14743520 bytes
UE4Editor!FEngineLoop::PreInit() + 9438 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.2\engine\source\runtime\launch\private\launchengineloop.cpp:1143]
UE4Editor!GuardedMain() + 236 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.2\engine\source\runtime\launch\private\launch.cpp:111]
UE4Editor!GuardedMainWrapper() + 26 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.2\engine\source\runtime\launch\private\windows\launchwindows.cpp:125]
UE4Editor!WinMain() + 249 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.2\engine\source\runtime\launch\private\windows\launchwindows.cpp:207]
UE4Editor!__tmainCRTStartup() + 329 bytes [f:\dd\vctools\crt\crtw32\dllstuff\crtexe.c:618]

I only have 4.0-4.2 installed as I haven’t had the time to really dedicate to it until recently. 4.0 seems to launch but 4.1 and 4.2 fail.

Edit: System specs for info - i7 4790, 16Gb RAM, 770 GTX, Asrock Z79e

Hi WolfSpinach,

Have you tried launching in the latest builds (4.4.3 or 4.5.0?) If this is not possible please follow the instructions in the following link in order to report a bug:


I’ll renew my subscription and test on the new versions, I was looking forward to playing with UMG anyway.

Occasionally Maya or Softimage’s user prefs get screwy and will cause them to crash or lock repeatedly so a common fix is to remove the user preferences folder. Is there an equivalent procedure in Unreal? Something that doesn’t require a full re-installation - I’m on 3rd World internet and it’ll take a couple of days to redownload :slight_smile:

Hi WolfSpinach,

Yes this is possible. Close UE4. Go to the drive where you installed UE4 (in this example “C”): Computer>Local Disk (C:)>UnrealEngine4>UE4>Engine>Config… Delete all contents within the Config folder then restart UE4. These items will be regenerated.

Hope this helps!