When a blueprint contains a function call from a custom blueprint function library, preforming a hot reload will prevent the blueprint from saving stating that the graph is linked to private object in an external package.

Steps to Reproduce
  1. Open UE4 Editor (Any Project)
  2. Add code to project based on BlueprintFunctionLibrary (CustomLib)
  3. Add the following to CustomLib.h
    	UFUNCTION(BlueprintCallable, Category = Test)
    		static void TestFunc ();
  4. Add the following to CustomLib.cpp
    void UCustomLib::TestFunc()
  5. Compile the code
  6. In the editor, create a blueprint based on Actor (ActorBP)
  7. add TestFunc node in event graph
  8. In Visual Studio, add float variable
  9. Use editor compile button to preform hot reload
  10. Open ActorBP and click the save icon

Blueprint fails to save. "Graph is linked to private object..." message

Blueprint saves after a hot reload

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Cannot Reproduce
ComponentUE - Gameplay - Blueprint
Affects Versions4.13.24.14
Target Fix4.17
CreatedDec 7, 2016
ResolvedFeb 21, 2017
UpdatedFeb 21, 2017