Map doesnt build lighting

Hi,
for some reason, pressing the build button in the editor doesnt build lighting anymore. I’m using the source version of 4.14.1 and have tried the following:

  • Validating and rebuilding the engine
  • Applying various answerhub solutions for similar problems, such as deleting the AppData/Local/UnrealEngine folder and cleaning/validating the cache in the swarm agent.

It does also happen on fresh projects. This is log of SwarmAgent:

02:22:18: Starting up SwarmAgent ...
02:22:18:  ... registering SwarmAgent with remoting service
02:22:18:  ... registering SwarmAgent network channels
02:22:18:  ... initializing SwarmAgent
02:22:18:  ......... certificate check has failed
02:22:18:  ...... initializing cache
02:22:18:  ......... using cache folder 'C:/Program Files (x86)/Epic Games/Source4.14/Engine/Saved/Swarm\SwarmCache'
02:22:18:  ......... recreating SwarmAgent cache staging area
02:22:18:  ...... initializing connection to SwarmCoordinator
02:22:18:  ......... using SwarmCoordinator on RENDER-01
02:22:21:  ......... SwarmCoordinator failed to be initialized
02:22:21:  ...... initializing local performance monitoring subsystem
02:22:21:  ... initialization successful, SwarmAgent now running
02:22:21: [Interface:TryOpenConnection] Local connection established
02:22:21: [Interface:OpenJob] Error: Der Wert darf nicht NULL sein.
Parametername: value

‘Der Wert darf nicht NULL sein’ translates to ‘This value must not be NULL’

Might firewall be a culprit ?

try disabling any antivirus or windows firewall and try rebuilding

I didnt think it could be a firewall issue, but just now i tried again with disabled firewall and it worked! Then i tried again with firewall enabled and it worked again…

No clue why, but it works again, thanks for your hint!

no worries bro . Well now U know how to fix this issue . will find something useful about swarm here

Hrmm, i am having the same problem on a new version of an old project. I reset my firewall, turned it off and back on – and also updated the project to .14 from .13 , but the lighting still fails to build after you click accept on both types of network connections? Any suggestion?