UE Randomly Crashes A Lot

So I’ve been working on a project lately which was going okay, no problems with crashes or whatever.
But now, I can’t get any work done. It’s horrible! :frowning:

I guess there’s something I’ve done to upset engine, or it just started to hate me out of nowhere but it crashes a lot out of nowhere. crashes appear to be very random, it randomly happens while working on Blueprints, compiling, saving, pressing Stop after playing… It just crashes at any given moment, so I have no idea what problem is.

I’ve got crash report right here: Crash report UE4 - Pastebin.com

Hope you guys can help. And this reminds me I need to set up VersionControl asap…

Bumping to make sure it gets seen by staff…

Hi Serellyn,

We believe this crash is related to one we have reported in UE-16935, but call stack is slightly different so I’ve created a second report under UE-18697 to track it once fix is implemented. We expect fix to go live in 4.9 when that is officially released, but if you’re using a source build you can grab this change:


or test project in Master branch.

It appears crash is related to compiling and/or saving AnimBP and/or Character using that AnimBP, and possibly only if they reference each other in explicit casts. I’m not certain if you’ll be able to adjust these so that doesn’t happen, but it’s first place I’d look.

Hope that helps!

Thanks for info . I don’t know what I changed but it spontaneously stopped crashing.

Sounds good! I’ll keep tracking this regardless. If you get that same crash again, feel free to let us know here. Thanks!

Hey , it crashed multiple times again today, not sure if it’s because of same error but here’s log: MachineId:9011551A4B33D3F52DBF2491AADA1E62EpicAccountId:e75894d3c31b416eb7349b - Pastebin.com

That’s a different crash. When these crashes occurred, was it during Play in Editor? They appear to be a networking/replication crash; is this a Multiplayer game?

This crash is also already in our system (UE-16587), and it appears to involve seamless travel. Try disabling that in your GameModes and see if that crash ceases.

We have some reliable reproduction steps, but I’d like to hear any additional information you have so I can add it to report. I’ll post here when I see any update on that.

I doubt it. That appears to be a logic problem, with what may still exist between levels that’s printing. We’d probably need to see it in project to find cause. If you’re able to determine it’s a bug, please feel free to open a new Bug Report post for it, though we may need to get a copy of project to really narrow it down.

It’s indeed a multiplayer game. most weird thing is that, after it crashed I restored it, and pressed play again to see if it would crash again but now it just worked.

There’s just one thing tho, since that crash (or around that time) I started to have very weird behavior on my Character Blueprint. I’ve described problem here, might this be related? Print showing in Levels where it should not - Blueprint - Epic Developer Community Forums

This engine just loves crashing and ruining our work it seems, only thing its good at.
Just as I was progressing smoothly and after I moved a few files around and deleted some, it ruined my project and everytime I try loading up my print now it always crashes.

I started a new project and decided to move my assets one by one starting from my character and animations and it started crashing because of animation import now which is strange, add better debugging options to solve such errors, I can’t do anything now, all my work is just lost??

I’m sorry if this sounds not nice, but at this rate I might just switch to another engine if risks of this happening are lower.


If you are experiencing a crash, please create a new post in bug reports section and provide as much info as possible, including:

  • Your Machine ID and ensure to hit Send & Close on report.
  • logs from your project’s Saved->Logs folder
  • Repro steps if you have determined a solid repro case.

Thank you