Crashes when i hit play

I made a project, coded in it in blueprint, saved, sent a copy to my schools O drive, and tried to open it on my laptop. copied file crashed, so I came back to my original and now it’s crashing too. this is crash report:


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

Assertion failed: TargetDelegate [File:D:\BuildFarm\buildmachine_++depot+UE4-Releases+4.6\Engine\Source\Editor\UnrealEd\Private\Kismet2\BlueprintEditorUtils.cpp] [Line: 5407]

KERNELBASE + 26840 bytes
UE4Editor_Core + 3092349 bytes
UE4Editor_Core + 1597688 bytes
UE4Editor_Core + 1479058 bytes
UE4Editor_UnrealEd + 9502651 bytes
UE4Editor_Engine + 5012673 bytes
UE4Editor_UnrealEd + 9881575 bytes
UE4Editor_UnrealEd + 4557402 bytes
UE4Editor_UnrealEd + 4660963 bytes
UE4Editor_UnrealEd + 1801811 bytes
UE4Editor_UnrealEd + 6686342 bytes
UE4Editor!FEngineLoop::Tick() + 3876 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.6\engine\source\runtime\launch\private\launchengineloop.cpp:2214]
UE4Editor!GuardedMain() + 479 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.6\engine\source\runtime\launch\private\launch.cpp:131]
UE4Editor!GuardedMainWrapper() + 26 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.6\engine\source\runtime\launch\private\windows\launchwindows.cpp:126]
UE4Editor!WinMain() + 249 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.6\engine\source\runtime\launch\private\windows\launchwindows.cpp:202]
UE4Editor!__tmainCRTStartup() + 329 bytes [f:\dd\vctools\crt\crtw32\dllstuff\crtexe.c:618]

Is there any way to recover it?

Hi Ironmonger42,

This is a known crash that occurs in 4.6 that involves Event Dispatchers. If you’re using an Event Dispatcher in one of your Blueprints, you’ll need to remove that Blueprint from your project and then it should start up again. Otherwise, if you’re allowed to update to 4.7 for your project, opening a copy in 4.7 should resolve crash without requiring removal of problem BP.

Hope that helps!