Project crashes with 4.4.3

My project loaded fine in
4.4.2-2289767+++depot+UE4-Releases+4.4
now crashes on startup with
4.4.3-2296771+++depot+UE4-Releases+4.4

The project was struggling with two major issues: when it worked then it had these warnings and recently any BP work made the project crash on startup with these errors. However before updating from 4.4.2 to 4.4.3 the project was rolled back to and kept in a working state so non BP work could be done. And that version is not loading anymore.

I can send the link to project in email.

logs.

Hi ,

Does this occur on a blank project with no additional content? Additionally, are you able to load the project if you pull out the maps folder from the project filepath?

An empty project and the content examples work fine. Removing the maps folder didn’t help. If I remove the interface BP for the custom gamestate (which is used extensively in many other classes) then the project loads up, with tons of error messages of course.

Hi ,

What do you have in the interface? Does a new interface cause the error?

The interface is used by classes to call data management related functions. Removing the gamestate class itself does not help with the crash so it’s probably not related to that BP. My guess is that when the interface is not found then none of the other, system critical classes (pawn, controller, missions, etc) get compiled including the one(s) causing the crash.
I’ll go through every BP asset and see if I can find one which, when removed, allows the project to load in some state.

I found several BP classes which when removed the project loads although everything is broken as related classes don’t compile anymore. I collected the classes mentioned in the error messages for each file and compared them. The list varies somewhat but almost always contains my base class for weapons and pawns, which is hardly surprising as they are the foundation of the game logic.
This is a dead end and I’m not sure what to try next. Is there a way to get back 4.4.2 somehow?

Unfortunately I do not believe that is possible at this time. Have you tried moving the pawn and weapons to a separate project to see if they cause the same errors there?

I copied the pawn and weapon classes to an empty project. The project loaded but as soon as I attempted to open one of the classes the editor crashed with pages of missing assets. Fair enough. I kept copying over more and more stuff. After a while the pawn class was editable but didn’t compile as there still were missing types, interfaces and so on. Then I finished transferring everything necessary for a compile and now the editor crashes when trying to open the pawn BP. (I left the config files untouched so they do not reference my game mode, pawn, etc. Probably that’s why the editor loads at all.)

Crash dump

What file was the last file you migrated over before the crash occurred?

It seems the issue is rooted in a leaf on the weapon branch: “MouseGun”, a data-only asset extending the base weapon. If I remove it then the project starts and blueprints can be edited in spite of the several missing assets errors. I can even copy it back while the editor is running and it keeps working properly, until restart.

Now I’m trying to remove all references to MouseGun: editing default properties was easy but I still have two load errors listing two classes which do not reference MouseGun at all, only its parent class. I made sure I recompiled and saved everything but those two errors persist and I don’t know how to make them go away.

While I still have no idea what caused this problem here are the steps which fixed it:

  • Find the asset which is when removed allows the editor to start. Make sure that you deal with a leaf class and not its parent. (The removal of the parent class will prevent the problematic child class from compiling but might cause more damage than necessary.)
  • Check the log for missing asset errors. For stuff directly referencing the deleted class (actors placed on the map included) set the related property to something other than ‘none’ the back to ‘none’. (The ‘none’ displayed right after loading with errors seems to mean “class X which is missing”, maintaining a reference.)
  • Change something in the parent class of the removed asset, compile and save.
  • Restart the editor. Hopefully there won’t be any load errors related to that certain asset.
  • Copy back the removed class and restore references to it, compile save, quit. The project should load up and function fine.