"Failed to resolve validation session" when launching session, doesn't point out any errors or files

General Issues and Bug Reporting
1

Summary

When I try to launch the session, specifically during “Creating Modules” i get a “Failed to resolve validation session” error. There aren’t any files or errors shown in the Message Log, but here’s what the Output Log says during the error:

LogValkyrie: Error: FlowStep_ResolveSessionCandidates(): Failed to resolve validation session with error [{
“host”: “content-service.bfda.live.use1a.on.epicgames.com”,
“method”: “GET”,
“path”: “/api/content/v4/validation/session/71215862-3b59-4a82-ac80-8a87ac056dd8/resolve”,
“errorCode”: “errors.com.epicgames.content-service.module_validation_session_invalid_operation”,
“errorMessage”: “session 71215862-3b59-4a82-ac80-8a87ac056dd8 cannot be resolved until all candidate validations have been trigerred”
}]
LogOutputDevice: Warning: Script Stack (0 frames) :
LogOutputDevice: Error: === Handled ensure: ===
LogOutputDevice: Error: Ensure condition failed: Task == this [File:Z:\UEVFS\Root\Engine\Source\Runtime\Core\Private\Misc\SlowTask.cpp] [Line: 149]
LogOutputDevice: Error: Out-of-order slow task construction/destruction: destroying ‘Uploading Projects…’ but ‘Matchmaking …’ is at the top of the stack
LogOutputDevice: Error: Stack:
LogOutputDevice: Error: [Callstack] 0x00007ff7891cbd22 UnrealEditorFortnite-Win64-Shipping.exe!UnknownFunction

It should be mentioned that there are more people experiencing this issue, not just me: Starting Session in UEFN impossible | Validation Error

Please select what you are reporting on:

Unreal Editor for Fortnite

What Type of Bug are you experiencing?

Matchmaking

Steps to Reproduce

Start the session

Expected Result

Session starts normally

Observed Result

“Failed to resolve validation session” Error

Platform(s)

PC

2

Hi @Flak could I get a ticket on this? I can’t start the session on my proejct at all.

3

FORT-960855 has been created and its status is ‘Unconfirmed’. This is now in a queue to be reproduced and confirmed.

4

How you going with this ?

Came across a slow task error that was caused by the resource override settings, the curve name was selected but the row name was not selected and it caused an error with slow task.

Use the show only errors filter on the output log after you attempt a launch, its easier to spot stuff… if its there

5

I filtered only Errors in the Output Log and found out there was another error just above the one I posted. It led me to a single file and the session now starts after deleting it.

Looks like my issue was a clone of this one

1 Like
6

Good Work, you’ve gone so many days without a launch, that hurts.

yeah I only found that filter the other day, must have recently been added, makes it way easier to find stuff.