Swarm failed to kick off and a solution by us

Error message: “Lighting build failed. Swarm failed to kick off”

Only one swarmagent.exe running and firewall has been disable

We found a solution to kill this problem:

  1. Create a new empty map

  2. Show all static meshes under “content” by the filter “StaticMesh”

  3. Place a part of the static meshes from the beginning into the new map, then build

  4. If lighting build was successful, delete all the actors in the map and place another part of static mesh under “content”, and so on

  5. If lighting build was failed, delete all the actors in the map and place less static mesh of the above selection in Step 3, we would found, lighting build would be successful

  6. An so on, After placing all of the static meshes under “content” and build successfully, close the new map without saving and reopen the map we needed

  7. Lighting build would be successful ! Amazing ?

So what we think is maybe the problem is caused by SwarmAgnet Cache? Can UE4 development team find out somthing ?

—From China UMU UE4 Technology Team

99% of the time when you get “Lighting build failed. Swarm failed to kick off”, it is because you need to build UnrealLightmass from Visual Studio.

It appears that you are seeing something different. When Swarm fails, there should be an error code or description. Do you have that?

Thanks.