Ive had a problem with Swarm Agent throwing a IO error, saying that a material (Mtrlgz) is used by another process.
No solutions found on answerhub that worked.
Finally i found this solution for me:
- Duplicate Level
- Build (Is gonna fail)
- Remove EVERYTHING in the world outliner.
- Build and Cancel before it finishes (you must let it export all light data)
- Doubleclick that same level (the duplicated) in the contentbrowser to open it, when promted do NOT save! (you do not want to save your removal of everything in the level)
- you have have your duplicated level with everything working! Click build and Tadaa! light is building.