On copying and duplicating a blueprint, to move it to another folder and rename. Functions within the new blueprint look ok at first, but on 1st compile a lot of them have warning, could not find function.
GOing through by hand and repulling off the nodes and adding the funcitons works to fix it, but it’a anoying when have a lto of funcitons to do. Copying and Duplicating of Blueprints both appear broken.
This is build 4.7.3 from the launcher. Blueprint Only project.
Hi ,
It looks like you have copied across the nodes that will call the functions defined in your original blueprint but you have not copied the functions themselves. The function section in the My Blueprint tab on the left of your screenshot is the clue I used here. As I understand it, functions exist as their own graph and are compiled separately from the main event graph and are not nested within it. The nodes that are causing the warning are indicating that there is no graph of the function for them to refer to.
Unfortunately I think the only way around this is to create a new function with the same name, inputs and outputs as the original (such as Play Sound) and then copy across the internals of the function from your source blueprint and link up the nodes correctly.
Another solution that might help in some cases is the collapsing of nodes within an event graph will allow them to persist and be copied across but you obviously lose the re-usability that functions afford you. If it suits as well, maybe look into whether Blueprint Function Libraries could help. They are global and can be used across Blueprints in your project.
That’s not it. The blueprint functions were copied. It was the functions that were from other blueprints that weren’t recognized. I had to pull off the pins again and choose the same function, which was then recognized.
This is a bug in the copy / duplicate behavior, or the feature was not completed. Either way, it’s a bug.
Hey ,
Are you copying the functions and nodes from within a blueprint or are you duplicating the whole entire blueprint and moving it between folders?
Thanks!
Hey ,
I haven’t heard from you in over 4 days. With that being said, I must close this thread at this time. If you’re still experiencing trouble, please respond back to this thread with additional information.
Thank you!
It was both duplicating the entire Blueprint and moving it. This should be a bug. In the future I won’t try to copy a Blueprint but will just make a new one.
Hey ,
Have you tried duplicating and copying blueprints since 4.7.4 has been released? That’s the version of the Engine which I’m working in now. I haven’t been able to successfully reproduce the issue that you’ve mentioned.
I have duplicated a blueprint to a new folder and compiled without errors. I have also duplicated and renamed the blueprint, which is in a new folder and compiled it without any errors. I’ve also copied the blueprint to a new folder and compiled it without any errors, and for my final try, I copied the blueprint into the new folder and renamed it, compiling without any errors.
If I’m attempting to reproduce this issue any differently than you, please let me know so that I can make adjustments and get this bug reproduced and over to the developers.
Thank you. 
Getting exactly this in 4.6: dupe blueprint and a bunch of functions that are defined in other BPs get this warning. Ignoring it and restarting the editor causes a crash whenever you open the BP.
Hello ,
Have you created a copy of your project and tested this in 4.8 Preview 4? There have been a lot of changes implemented over the past few releases that may resolve the issue you’re currently experiencing.
Thanks!
