Updating loads of BP after version upgrades - what a nightmare!

We have quite a large BP-based project that works fine when running in the editor as well as from a packaged build. We started with this project several UE versions ago and always updated the project to the latest engine version - which always worked fine. However, now we noticed that apparently since one of the last engine version upgrades the BP functions are not being called in standalone mode any more - they all do compile fine w/o errors, but they are just not being called. So the whole project does not work any longer.

I wrote to Epic support and asked them how to proceed, but unfortunately they told me there is no way to automatically fix all those BP assets. We would need to re-create all of them from scratch (i.e. create new BP assets for each existing asset and copy over all functions and macros and BP graphs).

But frankly that’s a horrible “solution”! We use several BP and UMG assets in the project, combined they have hundreds of functions and macros. Re-creating all these assets from scratch and copying over all their content would take us ages. Moreover we cannot just c&p the assets and BP graphs, as due to copying they become new BP classes, so all the references and parameters in the original assets, which are of the old BP types, would need to be updated by hand as well.

Is there really no other solution? This is a big problem for us - we are a very small team and re-creating all these assets from scratch would take us weeks. We do not have the man power to do that properly in time. And it seems to be error prone as well. Please help, we are out of ideas here :frowning:

You don’t get warning logs about the broken blueprints? Nothing??

This is the first time I read about this, Blueprint shouldn’t stop working for no reason without any warning signs of what is going on.

Yes, I never saw such a behavior either. There are no errors at all, the BP assets all compile fine. And everything works fine too - just not in standalone mode. I feel quite lost here …

watch the output log in play mode (different from the message log), that prints everything from network errors to window clicks.

Always have Output Log panel open in editor :slight_smile:

Sure, I have, no errors, no warnings :frowning:

Hey, thanks for your feedback! Unfortunately Epic has not told me many details. I’ve sent them my project and they just said "yes they can reproduce the issue, it seems it must have happended due to one of the engine upgrades. But no more details, which version or which problem exactly etc.

As for the custom call stack: That’s the thing, not a single function is being called. But without error message, they are just not being called at all. But as said, the logic itself is 100% correct, it’s working fine in PIE and packaged build, just not in standalone, in which basically nothing is happening :frowning:

If you really have no other choice but to remake Blueprints, this might be useful to mitigate a little the headache :

Some things work differently in standalone… For instance:

to conserve memory I recently converted object references on my data tables to soft object/class references and load them at runtime using a synchronous load function I exposed to BP. Worked fine in editor. But it turns out, that was because in the editor those assets were already loaded. Running in standalone, the game failed to load my assets causing a number of issues.

my point is, if your functions aren’t even getting called, maybe there is some overarching issue like this holding things up. There has to be something broken along the way. I doubt rebuilding your blueprints from scratch is going to fix what’s going on.

You just might get a result if you create a blank project and migrate all your stuff from your bad project into it. This has worked for me in the past and also worked for a chap on answerhub whose packaged game would not use steam. It is not fun but a lot better than re-creating. I don’t know why this works but sometimes at least it does.
Good luck.

That might help, I will have a look, thanks!

I am not sure about that - I copied over one or two BP classes and their functions into new BP functions, and then they have been called in standalone mode as well.

Ok I tried your tool, and it could indeed help me with my task.
However, I noticed that it does not work for all properties, i.e. a few of them are not recognized in the SOURCE tab so they are not being copied over.

Are there any limitations to this tool?

Variables pointing to components or pointing to null objects are ignored :slight_smile:

I understand. But anyways, this tool is of great use for us, thanks a lot!
(should be standard in UE editor btw.)