Niagara VectorFields do not function properly since "Fix CPU Access" changes are not persistently saved. After every Editor restart or reopening projects, the Niagara-VectorField driven Emitter and Emitter-Systems are not running and you have to apply the fix again.

This was reported and tested in 4.24.2 (CL-11100242). This was reproduced in 4.23.1 (CL-9631420) and Main 4.25 (CL-11152609)

Steps to Reproduce
  1. Open the UE4 Editor and create a Blank template project
  2. Downliad the attached Vector Field asset and add it into the project
  3. Enable the Niagara plugin and restart the Editor
  4. Create a Niagara Emitter and a System based on it
  5. In the Niagara System add SampleVectorField and ApplyVectorField under Particle Spawn
  6. For the Vector Field select the one we added earlier
  7. A CPU access error is shown and nothing is immediately working
  8. Press FixNow for getting CPU access for the VectorField, compile, save, close, and restart the project
  9. Open the Niagara System and click SampleVectorField

Results: A fixable, but not saveable CPU access error, that makes it impossible to use VectorFields in Niagara.
Normally you can close the UE4-Editor and everything is saved, but it doesn´t save the fixed CPU access!

Expected: Fix CPU Access is persistently fixed

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Won't Fix
ComponentUE - Niagara
Affects Versions4.
CreatedJan 31, 2020
ResolvedAug 31, 2021
UpdatedAug 31, 2021
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