Blocker - UEFN unable to Launch Session as of latest update

Please select what you are reporting on:

Unreal Editor for Fortnite

What Type of Bug are you experiencing?

Other

Summary

Unable to launch Session after latest update

When I click the “Launch Session” button in UEFN, one out of three things happen:

  1. Fortnite shows up a loading screen, after which I’m being returned back to the Launcher. In UEFN, it shows as “Session Connected”, but Fortnite didn’t load anything.
  2. I get a “Connection Error” in Fortnite, and the Session is canceled.
  3. My Island is opened in Fortnite, but there are no Assets loaded, and when trying to exit the Session, the game freezes, requiring me to force quit Fortnite using the Task Manager.

This is a major issue blocking me from working on my current project.

Steps to Reproduce

Click “Launch Session” and observe that, in fact, the Session does not launch.

Expected Result

“Launch Session” successfully launches a Session.

Observed Result

“Launch Session” does not launch a Session.

Platform(s)

PC

Additional Notes

Excerpt from the Output Log:

LogGameFeatures: Error: Dependency file:…/…/…/FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:…/…/…/FortniteGame/Plugins/GameFeatures/STW/STW_Irwin/STW_Irwin.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:…/…/…/FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:…/…/…/FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:…/…/…/FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:…/…/…/FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:…/…/…/FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:…/…/…/FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:…/…/…/FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogValkyrieAccount: [UValkyrieOnlineInstance::ApplyUserPreferredQoSRegion] Region Auto: ASIA
LogSlate: Warning: Slate: Had to block on waiting for a draw buffer
LogOnlineSession: Warning: MCP: FindSingleSession request failed. Invalid response. code=404 error={
“errorCode” : “errors.com.epicgames.modules.matchmaking.unknown_session”,
“errorMessage” : “unknown session id 2b75b61b7ac944e6b45bed68d1206df4”,
“messageVars” : [ “2b75b61b7ac944e6b45bed68d1206df4” ],
“numericErrorCode” : 12101,
“originatingService” : “fortnite”,
“intent” : “prod-live”
}
LogOnline: Warning: OSS: Async task ‘FOnlineAsyncTaskMcpFindSingleSession bWasSuccessful: 0’ failed in 0.242982 seconds

I have the same problem.

LogValkyrieSummary: No active session for current user. Creating new session.
LogValkyrie: Play succeeded.
LogSlate: Warning: Slate: Had to block on waiting for a draw buffer
LogValkyrie: ProjectSizeRequest for ef802c66-44d1-7c14-50ca-118ea16ca38d: GetProjectContentPackage
LogValkyrie: ProjectSizeRequest::GetProjectUploadSize for ef802c66-44d1-7c14-50ca-118ea16ca38d
LogValkyrie: ProjectSizeRequest::GetProjectDownloadSize for ef802c66-44d1-7c14-50ca-118ea16ca38d
LogGameFeatures: Error: Dependency file:../../../FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:../../../FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:../../../FortniteGame/Plugins/GameFeatures/STW/STW_Irwin/STW_Irwin.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:../../../FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:../../../FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:../../../FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:../../../FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:../../../FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:../../../FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogValkyrieAccount: [UValkyrieOnlineInstance::ApplyUserPreferredQoSRegion] Region Auto: NAE
LogValkyrie: ProjectSizeRequest::Cancel for ef802c66-44d1-7c14-50ca-118ea16ca38d - Content (re)cook error errors.com.epicgames.pre-processing.failed.
JOB_ID=850156e6-6a80-453a-9c27-5a7ca8c6174f
LogOnlineSession: Warning: MCP: FindSingleSession request failed. Invalid response. code=404 error={
  "errorCode" : "errors.com.epicgames.modules.matchmaking.unknown_session",
  "errorMessage" : "unknown session id 2b62af305600482f8d98a3f4661ae316",
  "messageVars" : [ "2b62af305600482f8d98a3f4661ae316" ],
  "numericErrorCode" : 12101,
  "originatingService" : "fortnite",
  "intent" : "prod-live"
}
LogOnline: Warning: OSS: Async task 'FOnlineAsyncTaskMcpFindSingleSession bWasSuccessful: 0' failed in 0.065969 seconds
LogGameFeatures: Error: Dependency file:../../../FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:../../../FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:../../../FortniteGame/Plugins/GameFeatures/STW/STW_Irwin/STW_Irwin.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:../../../FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:../../../FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:../../../FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:../../../FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:../../../FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:../../../FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogValkyrieAccount: [UValkyrieOnlineInstance::ApplyUserPreferredQoSRegion] Region Auto: NAE
LogNet: Warning: Channel name will be serialized as a string: ValkyrieBeacon
LogValkyrieSummary: Valkyrie Beacon Connected!
LogValkyrieSummary: Connected to Session: 390ce02acdf24e36925665670f07c1b6
LogValkyrieSummary: Session Setup Complete. About to Send Content!
LogValkyrieSummary: Checking for if the project can be uploaded
LogValkyrieSummary: Starting Project Upload - https://content-service.bfda.live.use1a.on.epicgames.com/project/#/4639a73b-41e1-bfc0-cb3d-a5abcc162768
LogValkyrieSummary: Syncing project MyFirstProject
LogSlate: Warning: Slate: Had to block on waiting for a draw buffer
LogValkyrie: Saving project source control settings to disk took 0.00 sec
LogValkyrie: Syncing project MyFirstProject with content service took  0.49 sec
VerseBuild: Warning: C:/Users/18182/Documents/Fortnite Projects/MyFirstProject/Plugins/MyFirstProject/Content/Code/zone_manager_device.verse(238,9, 249,1): Script warning 2000: Unreachable code - previous expression is guaranteed to exit early.
VerseBuild: Warning: C:/Users/18182/Documents/Fortnite Projects/MyFirstProject/Plugins/MyFirstProject/Content/Code/zone_manager_device.verse(238,9, 249,1) : Script warning 2000: Unreachable code - previous expression is guaranteed to exit early.
LogValkyrieSummary: Starting to upload file for module creation
LogValkyrieSummary: Successfully created module
LogValkyrieSummary: Creating Module Version
LogValkyrieSummary: Sending Content Update
LogValkyrieSummary: Calling UpdateContent on Valkyrie beacon with: ProjectId(4639a73b-41e1-bfc0-cb3d-a5abcc162768) SnapshotId(9a94edca-2f92-4257-b7c9-59992c960947) ModuleId(ef802c66-44d1-7c14-50ca-118ea16ca38d) ModuleVersion(955)
LogValkyrieSummary: RPCing content cook request to server: ProjectId(4639a73b-41e1-bfc0-cb3d-a5abcc162768) SnapshotId(9a94edca-2f92-4257-b7c9-59992c960947)
LogValkyrieSummary: Project MyFirstProject up to date
LogValkyrie: ProjectSizeRequest::Prepare for ef802c66-44d1-7c14-50ca-118ea16ca38d
LogValkyrie: ProjectSizeRequest for ef802c66-44d1-7c14-50ca-118ea16ca38d: GetRootModuleInfo
LogValkyrie: ProjectSizeRequest for ef802c66-44d1-7c14-50ca-118ea16ca38d: GetProjectContentPackage
LogValkyrie: ProjectSizeRequest::GetProjectUploadSize for ef802c66-44d1-7c14-50ca-118ea16ca38d
LogValkyrie: ProjectSizeRequest::GetProjectDownloadSize for ef802c66-44d1-7c14-50ca-118ea16ca38d
LogValkyrie: ProjectSizeRequest::Cancel for ef802c66-44d1-7c14-50ca-118ea16ca38d - Content (re)cook error errors.com.epicgames.pre-processing.failed.
JOB_ID=850156e6-6a80-453a-9c27-5a7ca8c6174f
LogValkyrieSummary: Server Summary - Successfully activated content on all platforms

This is some sort of Verse error in the zone_manager_device.verse. line 238 to 249 You will need to go into Verse and compile again. Delete Zone_Manager_device code and compile again

Thats not an error, that’s just a warning due to an early return with some code I didn’t comment out.

I still have this problem.

The status of FORT-780313 incident has been moved from ‘Needs Triage’ to ‘Closed’. Resolution Reason: ‘Cannot Reproduce’

I have the same issue. Have you found any solutions?

hi @VortexCAKO ,
You have done this before but can you try Verify UEFN/Fortnite again

If there are any updates they will be applied as well

Verifying UEFN/Fortnite and a clean uninstall reinstall did not fix it for me.

I was able to get through it by opening and launching a session from a different project, then re-opening and launching the original, problematic project.

Hopefully this helps others!

can you help me with what this error means?

LogGameFeatures: Error: Dependency file:…/…/…/FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:…/…/…/FortniteGame/Plugins/GameFeatures/STW/STW_Irwin/STW_Irwin.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:…/…/…/FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:…/…/…/FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:…/…/…/FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:…/…/…/FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:…/…/…/FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:…/…/…/FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData
LogGameFeatures: Error: Dependency file:…/…/…/FortniteGame/Plugins/GameFeatures/SaveTheWorld/SaveTheWorld.uplugin failed to transition with error GameFeaturePlugin.StateMachine.Registering.Plugin_Missing_GameFeatureData

Could you please post in World Creation - Epic Developer Community Forums for assistance?

did you figure out how to fix this?

I am having the same problem…