Cooking content fails to include JsonBlueprintUtilities plugin

I am working on a game that has a dedicated server, I am at the point where I have included some blueprint nodes of the JsonBlueprintUtilities plugin in my blueprints, now cooking content for the dedicated server fails with errors like these

gInit: Display: LogBlueprint: Error: [AssetLog] E:\DedicatedFPS\Content\ThirdPerson\Blueprints\BP_ThirdPersonCharacter.uasset: [Compiler] In use pin  <Unnamed>  no longer exists on node  FromString . Please refresh node or break links to remove pin. from Source: /Game/ThirdPerson/Blueprints/BP_ThirdPersonCharacter.BP_ThirdPersonCharacter
UATHelper: Cooking (Linux): LogInit: Display: LogBlueprint: Error: [AssetLog] E:\DedicatedFPS\Content\ThirdPerson\Blueprints\BP_ThirdPersonCharacter.uasset: [Compiler] In use pin  JsonString  no longer exists on node  FromString . Please refresh node or break links to remove pin. from Source: /Game/ThirdPerson/Blueprints/BP_ThirdPersonCharacter.BP_ThirdPersonCharacter
UATHelper: Cooking (Linux): LogInit: Display: LogBlueprint: Error: [AssetLog] E:\DedicatedFPS\Content\ThirdPerson\Blueprints\BP_ThirdPersonCharacter.uasset: [Compiler] Could not find a function named "FromString" in 'BP_ThirdPersonCharacter'.
UATHelper: Cooking (Linux): Make sure 'BP_ThirdPersonCharacter' has been compiled for  FromString from Source: /Game/ThirdPerson/Blueprints/BP_ThirdPersonCharacter.BP_ThirdPersonCharacter
UATHelper: Cooking (Linux): LogInit: Display: LogLinker: Warning: [AssetLog] E:\DedicatedFPS\Content\ThirdPerson\Blueprints\BP_ThirdPersonCharacter.uasset: VerifyImport: Failed to find script package for import object 'Package /Script/JsonBlueprintUtilities'

Here is everything I did to get to this point:

  1. Built UE 5.1 from source code
  2. Started new C++ project from the third person template
  3. Created Server build target
  4. Setup everything needed to cross compile to linux
  5. Cooked content and built server, everything worked then
  6. Added JsonBlueprintUtilities plugin and set up a function that uses the “get Json from String” function from it, as soon as that’s added as part of the content that would get cooked (I added it in the player character blueprint) the cook fails.

I tried adding this ExtraModuleNames.Add("JsonBlueprintUtilities"); to my server target.cs file but still wouldn’t work.

I really need the json capabilities of this plugin, but I don’t need any of that for my dedicated server really, however it still tries to cook that content even if it’s in a function(custom event) that only runs on owning client. Any ideas what I’m doing wrong? I haven’t been able to find much about this issue online.

Some additional details to this issue:

  • Cooking content for windows also produces the same errors
  • I tried to package the Json Blueprint Utilities plugin by going to Window->Plugins then finding Json Blueprint Utilities and clicking the Package button, it failed to package and produced this error:
UATHelper: Package Plugin Task (Windows): Module 'MQTTCore' (Engine Plugins) should not reference module 'JsonBlueprintUtilities' (Plugin). Hierarchy is Plugin -> Project -> Engine Programs -> Engine Plugins -> Engine.

I’m not sure if this has to do with my main issue, could be related. Would appreciate any help or guidance on this, until then I will continue investigating.

Another issue is when I attempt to cook the content and then I close and reopen the project, when I look in my blueprints, any node that was using JsonBlueprintUtilities will become unrecognized like this:
image

When I right click and click refresh it goes back to normal

So I managed to fix this, all I did was just start over from scratch. Started a new project and redid the same steps, and everything works now.

Something I didn’t mention that I did during the development work on this project is that I bought some new RAM sticks and installed them into my PC, I installed 64gb of Ram on top of my 16gb of RAM, DDR4. I didn’t mention it because I didn’t think it mattered, but now I’m thinking maybe that had some effect on my project?

Anyway, starting over was a bit of a pain but glad to have this working now at least.