Map Crashed / Can't open any backups

I was working in blueprints and my map crashed. I can no longer open my map. I have been diligently saving daily copies of my project to always have a backup. None of these open - when I try the program just crashes and offers me a crash report that is no help. I then try to open backup files in the backup directory, and the same result. I can’t open any of my previous files in the project!!!

I had been thinking of teaching this to my high school class in the fall - but if the work crashes when experimenting (like students do) and the backups are non functional - I may just take my $ to unity.

Can you help me open up my project? I would gladly take a previous days file at this point - but I can’t open ANY of my files related to the project - > so hours and hours of work are for…nothing?

Hoping you have an answer.

Hi sherr,

I’m sorry you’re having this issue. Could you attach your dxdiag, LOG, and DMP files. If needed, below is a link explaining how to find all of this info.

First thing I want to say is I don’t fully know what I am doing, I am learning by doing and exploring. The problem is that in my learning (and mistake) I seemed to have poisoned my entire project project going back versions.

The issue seemed to be with a compile issue in the hud blueprint. I was able to get the project open (not the level) and delete the blueprint and I now have a static, non interactive version of my project. So I can’t give you what you are looking for.

My students (and I) are going to learn by breaking stuff. Doing thing incorrectly to learn how to do them correctly. I am starting to think that project blueprints are continually being updated and linked to all ue4 map files, regardless of file saving level versions - is this correct? When I updated my blueprints in V2, V3 of my project, breaking the project with some sort of issue, was I unknowingly ruining my older map verions that were using these blueprints?

If so, how can I get some sort of version control for a single user. I want what I do on Monday (map files, blueprints, etc) to be their own entity, and then what I do on Tuesday to be their own entity, so if I break one, I have something to fall back on. I have to think there is a way to do this?

I really like the blueprint option for more creative / artistic designers, but am still hampered by having to deal with multiple files (blueprints, levels, assets) that make up a single project. Could a future version of unreal look into a single project file that contains everything? I think it would make a lot of sense for more creative types, and I think solve the problem that I had today.

So yeah - how do I get better version silo’s so what I mess up on today, doesn’t ruin an entire project. I want to be able to fall back on a backup file - how can this be done with the ue4 workflow?

  • Thanks,

You can install a source control server on your machine. UE4 supports SVN and Git (2 popular ones). If you configure UE4 to that repository you can commit changes regularly and go back to working version

Hi sherr,

The easiest way to do this without using Source Control would be to create a new copy of your project for each iteration you need. You can do this in Windows Explorer (if you are using Windows) > Documents > Unreal Projects. This can take up quite a lot of space though, so I would make sure to delete any older unneeded projects as you go.

The next option of course would be Source Control. Using UE4 in conjunction with a program like Perforce you can set it up to do version control for you.

A bit about the different versions of UE4 and what happens when update:
When you create a project, that project will only work in the version of the editor that you created it in unless it is converted. For example, if I create a project in 4.2.1 it can only be edited using that version. If I download 4.3, I can convert the project. The best way to do this is to Convert by Opening a Copy, this will keep a 4.2.1 version just in case something went wrong and create a 4.3 copy.

With each version of UE4 we release, there are changes and improvements that may change or even break parts of your project when its converted. It’s best practice to not change versions in the middle of development unless you are prepared to fix issues that may arise.

I hope this helps, TJ

Would using something like perforce give me version control for not only the maps but also the connected blueprints? Are these treated as stand alone files in some directory?

I would then be able to go back in time and open up the backups, or older versions at will, save from there, and create a new branch (assuming unique file name)?


Also, the root of my issue came from creating a blueprint interface between my level blueprint and my hud blueprint. Can you point me to a blueprint interface tutorial? I need to access level blueprint variable in the hud blueprint.

Thank you,

Source control works down to a per file basis, but blueprints aren’t kept in their own file system. They are part of the .uproject you are working in. So you would need to regress to a previous version of the whole .uproject file.

There are quite a few tutorials for learning blueprints. A good place to start is our Wiki.

Epic Video Tutorials:

Written Tutorials:

Here is a fairly thorough explanation of the HUD Blueprints from our sample content:

thank you, I will give it a shot after dinner!