[4.7] - Blueprintable Component causes "Graph is linked to private object(s) in an external package" while saving a map

  1. Create Blueprintable Component file, i.e. Scene Component.
  2. Put this as component to Actor Blueprint.
  3. Use this actor in map.
  4. Compile BP Component, Compile Actor, save map. It’s fine so far.
  5. Edit graph of BP Component, compile it. Compile Actor, save map. Now I’m often getting error - map behaves like change BP Component is object “in external package”.

I found only one annoying workaround so far. Remove BP Component from actor, save actor and map. Insert this BP Component again, save actor and map. No errors.

Could be related to https://answers.unrealengine.com/questions/179442/470-461-inherited-macro-causes-graph-is-linked-to.html
It’s similar nonsense :wink:

I could provide more detailed repro and/or some files, if this would difficult to replicate. But it looks like common issue in fresh system of Blueprintable Components.

I am getting this exact same issue in 4.7.1.

I have not yet updated to 4.7.2 but maybe it is corrected in that release.

I’ve had this issue several times. It is usually followed by doing something it didn’t like. For instance, undoing something that was deleted. I am fairly certain at that point it is a corrupted BP and will need to be remade. I have seen this in 4.6 and 4.7, though 4.7 seems to have more crash bugs at the moment then Window XP.

An update: I found that a not-so-obvious circular dependency could cause this error. In one example: a function in a function library calling another function in the same function library.

This helped: Can't Save Blueprint (Referenced in /Engine/transient) - Programming & Scripting - Unreal Engine Forums

Same issue here too. I hope Epic releases a hotfix for this as it’s a huge cost on productivity for anyone making extensive use of the blueprint components.

Thanks a lot to miligram9 for posting both the repro and workaround, I just confirmed your keen observation and it works as suggested.

@Purecyn - AFAIK this particular issue is not related to any circular dependency, miligram9’s repro is accurate, blueprintable components indeed seem to be the root cause.

I have had this issue come up and i think i know why this error happens. First i will ask a question did any of you copy the component or duplicate a component?

i had this error about a week ago so i deleted a component until the save error went away then recreated them , and no problem.

i just had the same error about 5 minutes ago , right after i duplicated a static mesh component.
so im pretty sure if add a new component instead of trying to duplicate one you should be fine.

yup thats it i was just able to recreate the error again.

I just got this same error I copied components from one blueprint put them in another and re-named them however it apparently still tracks some data from copied component.

My Solution: Delete all copied components and re-create from scratch

oh christ… I guess it is time to resize & locate 18 spheres… >.<

I am frequently getting this error, when working with the savegame file in the construction script of the blueprint (does save game exist, load game from slot etc).

Putting it in the EventGrap and triggering it via BeginPlay helped.