Crash without a reason

Recently I have been working with blueprint interface, which made a whole project crash. Then I wanted to start that project, but it crashed again, but this time at start. After that I implemented the same blueprint mechanism which probably was the reason for the error, but worked fine in another blueprint.
Now i could start my original project by removing a blueprint, but I am still unable to open the other one without a crash.

My main concerns is that the error seems to have no reason to me, which means it could come again at any other projects.

Any help would be much appreciated.

Hello ,

I was looking over your issue. I had a few questions for you if you are still in need of assistance. Please feel free to answer the following questions if you would like further assistance and I will be more than happy to help.

Quick questions:

  1. Are you still experiencing this issue?
  2. If you are, What version of the engine are you using?
  3. I know you said that you didn’t understand why the engine crashed, however would it be possible for you to provide accurate steps to reproduce this issue?
  4. Have you tested this in the current version of the engine (4.6)?
  5. Could you provide screen shots of any blueprints that you may think is causing the crash?
  6. Can you provide the error message that you were referring to in your post?

Make it a great day


1.) I have found the blueprint that was responsible for the crash and I deleted it, so it does not come up anymore.
2.) -
3.) I guess you can easily re-create the issue by deleting an important blueprint interface, which has been added to multiple actors, for one characters and for some pawns.
4.) No, I haven’t, I experienced the crash with 4.5.1.
5.) No, because I don’t have the files. Not to mention the engine was unable to open it from editor.
6.) -

After all, I realised, that “force delete” is not a great idea to do, but thanks to Unreal, it had a copy of all blueprints, so I didn’t lose any important data. (Otherwise the project was only for learning purposes.)

Have a nice day.

Hello ,

With this new information, I did a bit of digging and found that this is a known issue and that a report (UE-6482) has been submitted to the developers for further consideration. I am happy to hear that your issue has been resolved. Thank you for all of your information and time. I will be marking this question as answered because the issue has been reported and resolved. However, if you feel that further discussion is needed please feel free to post any remaining questions on the subject and I will be more than happy to assist you.

Make it a great day