Unable to update Blueprint project from 4.0.2 to 4.1 or 4.2

I have a fairly old Content-Only (Blueprint-based gameplay) project that I can run successfully in 4.0.2, but attempts to open it in 4.1 are mostly broken and unstable, while opening the project in 4.2 completely fails.

I spent some time in 4.1 opening, compiling and saving out all my blueprints, but the game remains unstable and I’m unable to work in it at all.

4.2 simply fails to load any of my blueprints. Even right-clicking on them in the content browser crashes the editor.

I know this isn’t a terribly detailed report, but I don’t have much solid to report. I’ve submitted about 50 crash reports today between the two versions. I’ve attached the logs and .dmp files from 4.2. I can’t include 4.1 files as I’ve reverted my project in perforce after getting frustrated and wanting to make some progress on the design side.

Is there some way of seeing what’s wrong with the blueprints without having to simply start again from scratch or stay with 4.0.2 for the life of the project?link text

Are you using migrate? It seems safer to use that than to just copy content from one place to another.

That’s a good suggestion. I’ll give it a try and see what comes of it!

Okay, gave it a try and it’s still crashing as soon as I touch any of my blueprints.

Callstack:
!Id:

We apologize for the inconvenience.
Please send this crash report to help improve our software.

It happened to me too. I gave up and started over. I didn’t get a reply about it in my posts. I haven’t yet run into the project doesn’t open problem with my current v4.2 public release project, but I wonder if it is just a matter of time.
I started using ‘AlienBrain Essentials for Artists’ so I can rollback at such a time I cause my blueprints to stop working … hopefully that helps.

Out of curiosity, I tried to load a 4.0.2 project in 4.2. I got a message asking if I wanted to open a copy, because its safer. Crashed the editor.

Oops, spoke too soon. The editor disappeared for a while and then came back again. The 4.0.2 project appears to work fine. Try something- update your .uproject files by right clicking on them, selecting the 4.2 engine and reloading the VS files. Then in VS, hit “rebuild”.

Thanks for the tip, however it’s a content-only project and doesn’t have any source to compile. I’m wondering if that’s part of the issue as it doesn’t have a chance to fix linking errors is VS or something (Way above my paygrade)?

Sorry, you did say that in your post. Has it ever given you the option to open a copy of the project?

As in, not the original project, a copy that it makes for you to prevent problems? If it hasnt, I’d be tempted to try compiling 4.2 from source.

It did, and I did. It’s really just a copy of the project folder, nothing too fancy.

I guess the good news is that means the project is still intact. I’d probably still switch to the github version. If you just follow the instructions on the github page, step by step, it isnt going to give you any major headaches…

So, while not quite an answer to the issue, I did manage to resolve most of it and found a pattern of instability.
Here’s what I did to get my project up and running in 4.2:

  1. Created the project copy (I’m running Perforce, so this wasn’t totally needed, but I wanted to ensure I was working with a fully fresh project folder.)

  2. Moved the Blueprints folder out of the Content Folder (ALL my logic blueprints exist in here: pawn, gametypes, powerups, weapons, etc.) to a temp folder outside the project.

  3. Added my blueprints back one by one, starting with the most important (Pawn, gametype, HUD, etc.) until I ran into crashes. I payed close attention to the output log and saw where my errors were coming from. If An added blueprint made the game crash, I’d move it back to the temporary folder, and continue.

  4. Opened each Blueprint, compiled and saved. Those that referenced enums needed the switch on enum nodes to be refreshed to display the correct enum string.

5)Continued adding, compiling, adding compiling, testing until everything seemed to work again!

Eventually, I was left with all my core gameplay, but the issue seems to be :
Derived Blueprints with custom blueprint scripting. Derived blueprints that were data-only (Only changing default values) seemed to do just fine.
and/or
Redirectors and old, unused classes that had been cluttering up my project may have been causing issues.

While this isn’t a solution, it did get my old 4.0.2 game up and running in 4.2. YMMV