UE4 Crashes when playing in viewport

After editing a UMG blueprint i now crash all the time when i try to play in the viewport. After disabling the UMG and multiple other blueprints so they don’t execute i still crash. Everything was working fine until i made further changes to this UMG, the UMG blueprint contains a simple counter/timer.

I’m running 4.5.1

[link text][1]
Unknown exception - code 00000001 (first/second chance not available)

Assertion failed: Class [File:D:\BuildFarm\buildmachine_++depot+UE4-Releases+4.5\Engine\Source\Runtime\CoreUObject\Public\UObject\Class.h] [Line: 2504] 
ConstructObject called with a NULL class object

KERNELBASE + 37901 bytes
UE4Editor_Core + 3174852 bytes
UE4Editor_Core + 1677512 bytes
UE4Editor_Core + 1566866 bytes
UE4Editor_UnrealEd + 3752518 bytes
UE4Editor_UnrealEd + 4138599 bytes
UE4Editor_UnrealEd + 4429648 bytes
UE4Editor_UnrealEd + 4526262 bytes
UE4Editor_UnrealEd + 1893329 bytes
UE4Editor_UnrealEd + 6486374 bytes
UE4Editor!FEngineLoop::Tick() + 3524 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.5\engine\source\runtime\launch\private\launchengineloop.cpp:2129]
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]

Hello FusSionzZ97,

I have a few questions for you that will help narrow down what it is that is causing your issue.

Quick questions:

  1. Can you reproduce this in a clean project?
  2. If so, can you provide a detailed list of steps to reproduce this issue?
  3. Are you receiving any errors?
  4. If so, could you provide them in the next post?

I tried migrating my assets to a new project all was working until i connected up my first UMG blueprint then the issue came back. I have now updated to 4.6.1 recreated the same blueprint and now is working.


Hello FusSionzZ97,

I am happy to hear that your issue has been resolved. If the issue make a recurrence please feel free to update this post with any additional information that you have.

Make it a great day.