Lighting won't build (KBM & other solutions already tried)

Hi!

Thanks in advance to anyone taking a look. I know your instinct will be to point me to existing articles on this, as there are many. But of the dozens I’ve searched (both official and unofficial), no solution has worked for me so far. A link to my project: https://drive.google.com/drive/folders/1-GX3VO4Bex-MM3VfrNyrQxe7V3jp8hp6?usp=sharing

My lighting won’t build. It started a few months ago. It’s not just this project. I even started a project from scratch, and it wouldn’t build lighting on that either. I opened this same project on a separate computer, and lighting generated fine. I will post the Swarm log below, and then things I’ve tried. Now, depending on troubleshooting steps I’ve taken, sometimes the log changes and is able to successfully connect to Coordinator, for instance. But the failing certificate is interesting, and I’m wondering if that’s a hangup for which I’ve not found a solution.

2:54:20 PM: Starting up SwarmAgent …
2:54:20 PM: … registering SwarmAgent with remoting service
2:54:20 PM: … registering SwarmAgent network channels
2:54:20 PM: … initializing SwarmAgent
2:54:20 PM: … certificate check has failed
2:54:20 PM: … initializing cache
2:54:20 PM: … using cache folder ‘C:/Users/hperk/AppData/Local/UnrealEngine/4.27/Saved/Swarm\SwarmCache’
2:54:20 PM: … recreating SwarmAgent cache staging area
2:54:20 PM: … initializing connection to SwarmCoordinator
2:54:20 PM: … using SwarmCoordinator on HPERK209-DTOP
2:55:02 PM: [Ping] Communication with the coordinator failed, job distribution will be disabled until the connection is established
2:55:02 PM: … SwarmCoordinator failed to be initialized
2:55:02 PM: … initializing local performance monitoring subsystem
2:55:02 PM: … initialization successful, SwarmAgent now running
2:55:02 PM: [Interface:TryOpenConnection] Local connection established
2:55:02 PM: [Interface:OpenJob] Error: Invalid class


Things I’ve tried:

  • Updating. W10, Windows drivers, Intel drivers, NVIDIA drivers, display drivers
  • I ran an sfc /scannow to fix any corrupted files
  • Completely reinstalled the engine
  • Cleared cache in the DOTNET/Swarmcache folder
  • Changed Swarm directory, cleared its cache
  • Launched Swarm agent .exe from directory
  • Despite having no commercial antivirus, and exceptions into Windows Def for Swarm and Unreal, temporarily turned off firewall
  • Trying an earlier version of the engine, all the way back to 4.25.4
  • Since Swarm can ping Remote Agent but not Coordinator, I set Coordinator to my desktop name. But still resulted in error
  • Clearing C:\Users\AppData\Local\UnrealEngine\4.27\Saved\Swarm\SwarmCache and having it create a new directory
  • Enabling Developer Settings in Swarm Agent and setting EnableLocalPerformanceMonitoring to false

Computer specs:

Intel(R) Core™ i7-8086K CPU @ 4.00GHz
NVIDIA GeForce GTX 1080
16 GB RAM
Windows 10


Here is the solution:

Also read this article:

To fix this error I did this In PowerShell (Admin):

net stop winmgmt /y
winmgmt /resetrepository
winmgmt /salvagerepository
winmgmt /verifyrepository

Done. The lighting now builds successfully.

PS: If some commands were not necessary - please correct me.