Editor crashes when opening level


I’m not able to load my level file anymore, when I try to load it through File->open level, it pops up saying ‘Failed to open map file. This is most likely because the map was saved with a newer version of the engine.’ (It wasn’t saved with a newer version), and when I try to just double click the level file in the project files browser, it crashes the editor.

It was working perfectly fine several hours ago… what may have caused this is: starting to build the lighting, cancelling the build, clicking to close the editor and selecting yes when it pops up asking whether it should save the map, waiting till the editor is closed, restarting the computer. At least that’s what I did right before it started crashing.

I was using 4.5.1 version of the engine. Any help fixing this issue would be really appreciated, as I stupidly haven’t made any backups of the map file in about a week…

Here’s the crash report:


Unknown exception - code 00000001 (first/second chance not available)

Fatal error: [File:D:\BuildFarm\buildmachine_++depot+UE4-Releases+4.5\Engine\Source\Runtime\Core\Private\HAL\FileManagerGeneric.cpp] [Line: 608] 
Invalid BufferCount=0 while reading ..//..//..//..//..//..//Users//Ed//Documents//Unreal Projects//A3D

KERNELBASE + 37901 bytes
UE4Editor_Core + 3174852 bytes
UE4Editor_Core + 1677215 bytes
UE4Editor_Core + 690023 bytes
UE4Editor_Core + 808701 bytes
UE4Editor_CoreUObject + 848220 bytes
UE4Editor_CoreUObject + 1129316 bytes
UE4Editor_CoreUObject + 1161231 bytes
UE4Editor_CoreUObject + 930168 bytes
UE4Editor_CoreUObject + 1002266 bytes
UE4Editor_CoreUObject + 1424764 bytes
UE4Editor_CoreUObject + 1535630 bytes
UE4Editor_ContentBrowser + 1370711 bytes
UE4Editor_ContentBrowser + 1735106 bytes
UE4Editor_ContentBrowser + 1255123 bytes
UE4Editor_ContentBrowser + 1294632 bytes
UE4Editor_ContentBrowser + 1784182 bytes
UE4Editor_ContentBrowser + 1227254 bytes
UE4Editor_ContentBrowser + 1286539 bytes
UE4Editor_ContentBrowser + 1276022 bytes
UE4Editor_ContentBrowser + 1869215 bytes
UE4Editor_ContentBrowser + 1784767 bytes
UE4Editor_Slate + 818133 bytes
UE4Editor_Slate + 754699 bytes
UE4Editor_Core + 2505996 bytes
UE4Editor_Core + 2450091 bytes
UE4Editor_Core + 2510873 bytes
UE4Editor_Core + 2438466 bytes
user32 + 105425 bytes
user32 + 104666 bytes
UE4Editor_Core + 3157718 bytes
UE4Editor!FEngineLoop::Tick() + 3106 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.5\engine\source\runtime\launch\private\launchengineloop.cpp:2111]
UE4Editor!GuardedMain() + 479 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.5\engine\source\runtime\launch\private\launch.cpp:133]
UE4Editor!GuardedMainWrapper() + 26 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.5\engine\source\runtime\launch\private\windows\launchwindows.cpp:125]
UE4Editor!WinMain() + 249 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.5\engine\source\runtime\launch\private\windows\launchwindows.cpp:201]
UE4Editor!__tmainCRTStartup() + 329 bytes [f:\dd\vctools\crt\crtw32\dllstuff\crtexe.c:618]


Hi Ed,

Could you also include your LOG and DMP files? Follow the link below for directions on where to find them.

One thing to try is remember what assets you where working on/with before the crash started occurring. Make a clone of your project and then start removing .uassets from the project files while trying to load it in between each one.

Hi Ed_,

We haven’t heard back from you in a few days, so we are marking this post as Resolved for tracking purposes. If you’re still experiencing this issue, please feel free to post back here with additional information.