[4.6.1] Crash on Editor Launch

Hi, I’m experiencing an issue with the Editor in 4.6.1. Recently I started getting a crash when the editor launches with my project, the crash report comes out empty so I did a little bit of testing and managed to find that a character blueprint was causing the crash. After removing it from my project folder the editor would launch without a problem. Now, the thing is that I tried to open a backup project I had in 4.5.1, it had zero problems and would launch as expected; after I got the crash in 4.6.1 the backup project in 4.5.1 wouldn’t launch neither. I decided then to completely recreate my project from scratch in 4.6.1 and everything was working fine until I started getting the same crash today, with again a character (parent) blueprint. After removing it from my project the editor would launch.

This leaves me to think that I somehow changed some files used by both engines.

Here is what I’ve done since I installed 4.6.1 (the project was working fine in 4.6):

  1. Install & run 4.6.1
  2. Install & run Razer’s Synapse
  3. Install & run OBS (Open Broadcast Software)

I noticed the first time I opened OBS the editor crashed and that’s when I started to get the crashes so that’s my only theory. I’ve tried:

  1. Reinstall the engine (Both from Launcher & GitHub).
  2. Reinstall Visual Studio.
  3. Reinstall .Net 4
  4. Update Windows
  5. Update drivers
  6. Start a project from scratch.

I found this, which could lead to something:

Front End:

[2014.12.20-07.14.28:576][  0]LogDirectoryWatcher:Warning: Failed to begin reading directory changes for C:/Users/Pablo/Documents/Unreal Projects/MangoBackup/Binaries/Win64. Error: 0


[2014.12.20-07.14.46:614][  0]LogFileServer:Error: Sending empty file ../../../Engine/Config/Base.ini....

[2014.12.20-07.14.54:863][  0]LogWindows:Error: Windows GetLastError: The operation completed successfully. (0)
Assertion failed: PreviousCDO != nullptr [File:D:\BuildFarm\buildmachine_++depot+UE4-Releases+4.6\Engine\Source\Editor\UnrealEd\Private\Kismet2\BlueprintEditorUtils.cpp] [Line: 1062] 

Project Log:

KERNELBASE.dll!UnknownFunction (0x000007fefd3c940d) + 0 bytes [UnknownFile:0]
UE4Editor-Core.dll!UnknownFunction (0x000007fee0822f7d) + 0 bytes [UnknownFile:0]
UE4Editor-Core.dll!UnknownFunction (0x000007fee06b60f8) + 0 bytes [UnknownFile:0]
UE4Editor-Core.dll!UnknownFunction (0x000007fee0699192) + 0 bytes [UnknownFile:0]
UE4Editor-UnrealEd.dll!UnknownFunction (0x000007fede07cde3) + 0 bytes [UnknownFile:0]
UE4Editor-UnrealEd.dll!UnknownFunction (0x000007fede079664) + 0 bytes [UnknownFile:0]
UE4Editor-UnrealEd.dll!UnknownFunction (0x000007fede0766b8) + 0 bytes [UnknownFile:0]
UE4Editor-UnrealEd.dll!UnknownFunction (0x000007fede07cfe8) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee17e9070) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1837092) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18374db) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18537eb) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18b4985) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee187342f) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1872722) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1873792) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1872722) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1837cc4) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1851789) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18265b4) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18e1569) + 0 bytes [UnknownFile:0]
UE4Editor-BlueprintGraph.dll!UnknownFunction (0x000007fedd4a2758) + 0 bytes [UnknownFile:0]
UE4Editor-BlueprintGraph.dll!UnknownFunction (0x000007fedd4a2852) + 0 bytes [UnknownFile:0]
UE4Editor-BlueprintGraph.dll!UnknownFunction (0x000007fedd4e6531) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee185b242) + 0 bytes [UnknownFile:0]
UE4Editor-UnrealEd.dll!UnknownFunction (0x000007fede060b68) + 0 bytes [UnknownFile:0]
UE4Editor-UnrealEd.dll!UnknownFunction (0x000007fede060b70) + 0 bytes [UnknownFile:0]
UE4Editor-UnrealEd.dll!UnknownFunction (0x000007fede07ce3a) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee17e9070) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1837092) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18374db) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18537eb) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18b4985) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee187342f) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1872722) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1873792) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1872722) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1837cc4) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1851789) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18265b4) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18cb3ea) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee185b242) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee17b03b4) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee17c52d0) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1836f6c) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18374db) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18537eb) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18b4985) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee187342f) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1872722) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1873792) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1872722) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1837cc4) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1851789) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18265b4) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee185b242) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee17dcafd) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee17dc7fe) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee17f8496) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee17f7bea) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee185b242) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee17b03b4) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee17c52d0) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1836f6c) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18374db) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18537eb) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18b4985) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee187342f) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1872722) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1873792) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1872722) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1837cc4) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1851789) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18265b4) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18cb3ea) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee185b242) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee17b03b4) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee17c52d0) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1836f6c) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18374db) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18537eb) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18b4985) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee187342f) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1872722) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1873792) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1872722) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1837cc4) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee1851789) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee18265b4) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee185b242) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee17dcafd) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee17dc7fe) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee17f8496) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee17f7bea) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee185b242) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee17dcafd) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee17dc245) + 0 bytes [UnknownFile:0]
UE4Editor-Engine.dll!UnknownFunction (0x000007fed9e77593) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee17f7489) + 0 bytes [UnknownFile:0]
UE4Editor-CoreUObject.dll!UnknownFunction (0x000007fee185b242) + 0 bytes [UnknownFile:0]
UnknownModule!UnknownFunction (0x00003b3d095d39ff) + 0 bytes [UnknownFile:0]

Crash Report;

Any help I would appreciate. Thanks.

[UFE Log][1],
[Project Log][2],
[dxDiag][3]
[Crash Report][4]

im getting the same issue with my projects crashing on start up

In 4.6.1 as well? Some other people were getting something similar with character blueprints like in my case.

yeah in 4.6.1 s when it started for me. funny part is, is that converted my project to 4.7 before 4.6.1 started crashing and it works fine even with the same code i set up in 4.6.1. so what ever they did to 4.6.1 messed blueprints all up.

So you just converted it to 4.7 and works fine or you converted it before the crashes?

Alright, Imma give it a try in 4.7, thanks for the insight!

converted before the crashes since i converted before updating to 4.6.1

Hi Paleta,

I just wanted to confirm that this is only happening for you when you have both Razer Synapse and OBS installed? If you remove these two programs does the issue still occur?

Tim

Hi Tim,
I confirm that upon removing both programs from my computer, the engine still crashes.

Upon further investigation I found this:

4.6.1:

Assertion failed: PreviousCDO != nullptr [File:D:\BuildFarm\buildmachine_++depot+UE4-Releases+4.6\Engine\Source\Editor\UnrealEd\Private\Kismet2\BlueprintEditorUtils.cpp] [Line: 1062]

4.7.0:

Assertion failed: PreviousCDO != nullptr [File:D:\BuildFarm\buildmachine_++depot+UE4-Releases+4.7\Engine\Source\Editor\UnrealEd\Private\Kismet2\BlueprintEditorUtils.cpp] [Line: 1100] 

Found this information by pressing ctrl + v after the crash report pops up.
Both reports also include the crash Crash Report I attached.
I can attach the blueprint uasset file that is causing the issue if you want.

Actually if you can migrate that Blueprint into a new project with no starter content and reproduce the crash, then upload that project, that would be great.

If this isn’t possible, go ahead and upload the uasset and we will see what we can find.

Hi Tim, I somehow managed to open the project in 4.5.1 (editor crashes when I right click the file in Content Browser 99%of the times) and proceeded to migrate the file. Here is the project Link. I confirm that it still crashes when I try to launch the editor with this new project. The file I assume is causing the problem is in Content\Blueprints\MangoBlueprints\
It is named MyCharacter.

Hi Paleta,

Thank you for providing the project. I was able to see the crash that you described, and when I associated it with our latest internal build I was able to get the Engine to give me a callstack with more information in it. This appears to be an issue with a circular dependency. I started looking at the other Blueprints that were included in the project and discovered that I would get the same crash if I tried to open the I_CharacterPickup Blueprint Interface. If I removed one of these Blueprints from the project, I could open the other one successfully (though the interface did give some additional trouble when trying to open it without the MyCharacter Blueprint in the project).

Interfaces are usually helpful in avoiding circular references, but I am not sure it was completely successful in this instance. I did some digging to see if I could find out exactly where things were going wrong, but unfortunately I was not able to narrow it down much further. I think the Item Bag Blueprint may be involved as well. If you could, take a close look at those three Blueprints to make sure you do not have a circular dependency between them.

Our Blueprint team is working on reducing the impact of circular dependencies in Blueprints. Some improvements have already been released, but there is still a lot of work to do.

Tim

I see, I guess it was a mistake from my part. I will check the interwebs for circular dependencies and how to avoid them. Thanks for your time!

A circular dependency occurs when two or more objects depend on each other. For example, you have Blueprint A that requires Blueprint B in order to function. Blueprint B requires Blueprint C, and Blueprint C requires Blueprint A. The problem with this “circle” is that you cannot create an instance of Blueprint A without already having an instance of Blueprint B, which needs to have an instance of Blueprint C already available. Unfortunately, in order to have an instance of Blueprint C, you need to have Blueprint A already available, and you can see where the problem comes into the picture. Things can get really confusing when you have 5+ Blueprints forming a circle, since the bigger the circle is the more difficult it is to find out exactly what is causing the circle.

In general, removing one of the elements creating the circle will fix the problem. In the example above, if you can set it up so that Blueprint C no longer requires Blueprint A, then the circle is broken. Interfaces will often help with this, but it is still possible to end up with a circular dependency. Also, as I mentioned previously, we are working on reducing (hopefully eliminating) the negative effects of circular dependencies in Blueprints.

Oh thanks, that’s definitely a good starting point.