EDIT by Epic:
Hey everyone!
Could you try the following:
Delete
C:\Users\%USERNAME%\AppData\Local\UnrealEditorFortnite\Intermediate\ValkyrieUploadTemp
Restart UEFN and then try uploading again
Let me know if this works
I cannot launch a session in UEFN. In the Session Inspector, preparation, validation, and upload complete successfully, but the process fails at the versioning stage. Cooking, downloading, and launching are then canceled, and the session does not connect.
Unreal Editor for Fortnite
Other
Open the affected project in UEFN.
The session should launch successfully and allow me to playtest the project in Fortnite.
The versioning stage shows a red error indicator. Cooking, downloading, and launching are canceled, and the status indicates that no session is connected. I cannot start a playtest. The attached screenshot shows the failed stage, but no specific error message or error code is visible.
PC (Windows)
9597-0931-6909
3 Likes
The screenshot was not attached to my original post, so I’m adding it here. It shows the session launch failing at the versioning stage.
1 Like
SanDuKul
October 15, 2026, 12:49pm
4
Hello, I have the same issue
SanDuKul
October 15, 2026, 1:01pm
5
I don’t know if this helps, but here are my logs. This was working fine for a month and started failing right after this morning’s UEFN update (Oct 15). It seems to me that this only happens with my blueprints:
LogValkyrie: Error: FlowStep_ResolveSessionCandidates(): Candidate module [efbf8eb8-4058-04be-da49-8f86ad1f29e9] failed validation with error: [errors.com.epicgames.contentsentry.validationfailure][MODULE VALIDATION FAILED (job fb17fed7-723b-4ded-ade7-7e998eaed5a4):[CandidateApiJsonInvalid] Supplied candidate api does not match expected api: Differing redirectors: /efbf8eb8-4058-04be-da49-8f86ad1f29e9/Object/BP_LootManager.Default__BP_LootManager_C->/fortniterepocompany/Object/LootManagerAndVFX/BP_LootManager.Default__BP_LootManager_C <> /efbf8eb8-4058-04be-da49-8f86ad1f29e9/Object/BP_LootManager.Default__BP_LootManager_C->/efbf8eb8-4058-04be-da49-8f86ad1f29e9/Object/LootManagerAndVFX/BP_LootManager.Default__BP_LootManager_C]LogValkyrieFortniteEditorLiveEdit: Verbose: FValkyrieFortniteEditorLiveEdit::UploadEnd C:/Users/Labou/Documents/Fortnite Projects/fortniterepocompany/fortniterepocompany.uefnproject, FailedLogValkyrieFortniteEditorLiveEdit: Verbose: FValkyrieFortniteEditorLiveEdit::SetUploadRequired 1LogValkyrieFortniteEditorLiveEdit: Verbose: FValkyrieFortniteEditorLiveEdit::SetTrackingUploadRequired 0LogValkyrieRequestManagerEditor: OnUploadProjectsCompleted: C:/Users/Labou/Documents/Fortnite Projects/fortniterepocompany/fortniterepocompany.uefnproject, Failed
I too am running into this issue. The pop up i see is this, but what’s weird is while waiting to launch, it puts me to the default skin which is not the skin I use. When i try to run another project though it launches and works, just not the one I am currently working on.
1 Like
Thanks for reporting this
Hey everyone!
Delete
C:\Users\%USERNAME%\AppData\Local\UnrealEditorFortnite\Intermediate\ValkyrieUploadTemp
Restart UEFN and then try uploading again
Let me know if this works
1 Like
I am facing the same issue. Please resolve asap.
Deleting this now shows this error: Ensure condition failed: PushHelper.IsStarted() [File:Z:\UEVFS\FortniteGame\Plugins\ForEngine\Valkyrie\Source\ValkyrieEditor\Private\ScratchRepository\VkScratchRepository.cpp] [Line: 254]
Stack:
Ensure condition failed: ShouldPerformVerseBuild() [File:Z:\UEVFS\FortniteGame\Plugins\ValkyrieFortnite\Source\ValkyrieFortniteEditor\Private\ValkyrieStageProject.cpp] [Line: 3458]
Stack:
Following up internally, thank you!
@IconicStudio Could you send me your project for our engineer to debug this issue? You can send it to me privately here - this will create a direct message with me on the forums, nobody else has access.
Or feel free to send it to Alex and have him send it to me if you prefer that
This worked for me, I just had to restart UEFN.
1 Like
OKomili
October 15, 2026, 3:13pm
14
The same issue is happening for our project. We are unable to launch a session.
https://www.fortnite.com/@aokgames/9621-3035-2804
Did you try this?
Hey everyone!
Could you try the following:
Delete
C:\Users\%USERNAME%\AppData\Local\UnrealEditorFortnite\Intermediate\ValkyrieUploadTemp
Restart UEFN and then try uploading again
Let me know if this works
OKomili
October 15, 2026, 3:47pm
16
I have fully restarted UEFN and am still stuck at Versioning. FWIW I’m using the new Epic launcher, not sure if that’s a factor.
[LogForkManager] Fork manager disabled by cvarhttps://mcp-gc.live.fngw.ol.epicgames.com/fortnite/api/matchmaking/session/07b9f48645dd4f04acee3f33a55988b4 , sessionid=07b9f48645dd4f04acee3f33a55988b4
OKomili
October 15, 2026, 4:02pm
17
Apologies, user error, not enough coffee. I was restarting UEFN but was blind to the comment about deleting that folder. Deleting that now and it has fixed the problem on restart. Sorry for the confusion.
1 Like
FORT-1173189’s status has changed to ’Needs Peer Review’. A fix has been submitted, and is awaiting review by another team member.
I can’t make any progress on my Halloween map…
