At least 1 module failed remote validation

Summary

When I try to launch session , I get the error:
At least 1 module failed remote validation

Please select what you are reporting on:

Unreal Editor for Fortnite

What Type of Bug are you experiencing?

Other

Steps to Reproduce

  1. Open UEFN and press Launch session

Expected Result

Launch fine

Observed Result

Popup modal with ’ Unable to Play, text: At least 1 module failed remote validation’

LogValkyrie: Error: FlowStep_ResolveSessionCandidates(): Candidate module [a4c5b261-4cc7-9082-bfa1-70a7a5394581] failed validation with error: [errors.com.epicgames.pre-processing.download_failure]
LogValkyrieEditorAnalytics: Displaying Stats for Flow
LogValkyrieEditorAnalytics: =========================
LogValkyrieEditorAnalytics: Flow=Play
LogValkyrieEditorAnalytics: PlayFlow=69.351
LogValkyrieEditorAnalytics: ↳ PrepareProjectSourceData=52.974
LogValkyrieEditorAnalytics: ↳ UploadCookDownload=69.351
LogValkyrieEditorAnalytics: ↳ ValidationSessionInitializeContext=5.446
LogValkyrieEditorAnalytics: ↳ ValidationSessionRunLocalValidation=47.471
LogValkyrieEditorAnalytics: ↳ ProjectValidation=45.770
LogValkyrieEditorAnalytics: ↳ SyncWithContentService=1.706
LogValkyrieEditorAnalytics: ↳ UpdateProjectMetadata=0.337
LogValkyrieEditorAnalytics: ↳ InitSyncModules=19.383
LogValkyrieEditorAnalytics: ↳ StageProjectModules=3.587
LogValkyrieEditorAnalytics: ↳ GatherFilesForValidation=0.017
LogValkyrieEditorAnalytics: ↳ DownloadPublishedVerseFiles=1.209
LogValkyrieEditorAnalytics: ↳ ValidateProject=19.503
LogValkyrieEditorAnalytics: ↳ FindServer=9.965
LogValkyrieEditorAnalytics: ↳ MatchmakingToServer=6.712
LogValkyrieEditorAnalytics: ↳ ValidationSessionUploadCandidateSourceFiles=4.363
LogValkyrieEditorAnalytics: ↳ ValidationSessionCreateValidationSession=0.259
LogValkyrieEditorAnalytics: ↳ ValidationSessionCreateModuleVersions=11.505
LogValkyrieEditorAnalytics: ↳ ValidationSessionPruneScratchSpace=1.134
LogValkyrieEditorAnalytics: ↳ ValidationSessionResolveSessionCandidates=0.230
LogValkyrieEditorAnalytics: =================================
LogSlate: Window ‘Unable to Play’ being destroyed
Message dialog closed, result: Ok, title: Unable to Play, text: At least 1 module failed remote validation

Platform(s)

PC

Interesting to note; my friend does not have it when he’s trying to launch this project. Only me. Never had this error before.

Im having this same issue

This is insane, the error was randomly gone and appeared again today.
I have reinstalled UEFN, Fortnite AND Epic Games.

Zero luck unfortunately.

1 Like

I’m experiencing the same issue, i tried from the account of a colleague and he’s not having any issue at all launching session whatsoever as for me, even in newly created projects, it happens, I’ve done everything possible to remove that and its still there.

Here are the things I’ve done and that I’ve noticed

1- Validated assets in UEFN (reports completed, no issues).

2- Verified UEFN and Fortnite installations.

3- Reinstalled both UEFN and Fortnite.

4- Factory reset my machine.

5- Logged in on another machine (same issue).

6- Used another account (works fine, which suggests the issue is account-specific).

7- Checked Verse (no errors reported).

8- Tried creating new maps/projects (still cannot launch).

Mind you that when i revert back to old versions this doesn’t happen.

FORT-972567 has been created and its status is ‘Unconfirmed’. This is now in a queue to be reproduced and confirmed.

Mind you, i did the same with a colleague and he was able to launch the project WITH NO ISSUE, in the same machine, same internet, just different account, this is 100% a backend issue related to OUR accounts

LogEOSSDK: Warning: LogHttp: 000001861CF9F000: HTTP request timed out after 30.00 seconds URL=https://api.kws.ol.epicgames.com/v1/playtime/account/d0dcfaef7cca48faa1ffb0fdf8d70560/product/3fd15bc288014f698cca1a3d1f01c7af/heartbeat
LogEOSSDK: Warning: LogHttp: 000001861CF9F000: request failed, libcurl error: 0 (No error)
LogEOSSDK: Warning: LogHttp: 000001861CF9F000: libcurl info message cache 0 ( Trying 3.165.181.98:443…)
LogEOSSDK: Warning: LogHttp: 000001861CF9F000: libcurl info message cache 1 (Connected to api.kws.ol.epicgames.com (3.165.181.98) port 443)
LogEOSSDK: Warning: LogHttp: 000001861CF9F000: libcurl info message cache 2 (ALPN: curl offers http/1.1)
LogEOSSDK: Warning: LogHttp: 000001861CF9F000: libcurl info message cache 3 (ALPN: server accepted http/1.1)
LogEOSSDK: Warning: LogHttp: 000001861CF9F000: libcurl info message cache 4 (using HTTP/1.1)
LogEOSSDK: Warning: LogHttp: 000001861CF9F000: libcurl info message cache 5 (We are completely uploaded and fine)
LogEOSSDK: Warning: LogHttp: 000001861CF9F000: libcurl info message cache 6 (schannel: remote party requests renegotiation)
LogEOSSDK: Warning: LogHttp: 000001861CF9F000: libcurl info message cache 7 (schannel: renegotiating SSL/TLS connection)
LogEOSSDK: Warning: LogHttp: 000001861CF9F000: libcurl info message cache 8 (schannel: SSL/TLS connection renegotiated)
LogEOSSDK: Warning: LogHttp: 000001861CF9F000: libcurl info message cache 9 (Closing connection)
LogEOSSDK: Warning: LogHttp: 000001861CF9F000: libcurl info message cache 10 (schannel: shutting down SSL/TLS connection with api.kws.ol.epicgames.com port 443)
LogEOSSDK: Warning: LogHttp: Retry exhausted on https://api.kws.ol.epicgames.com/v1/playtime/account/d0dcfaef7cca48faa1ffb0fdf8d70560/product/3fd15bc288014f698cca1a3d1f01c7af/heartbeat
LogEOSSDK: Warning: LogEOS: Failed to connect to the backend. ServiceName=[PlaytimeTracking], OperationName=[PlaytimeControllerHeartbeat], Url=

@H6D6S nice debug, I never could of thought this would be account related, just reconfirmed your theory:

  1. I use my same machine for the full test
  2. Account A has the issue described as above, where it can’t launch the session
  3. Log out of account A → Log into account B
  4. Launch session works fine.

Thanks for sharing, much appreciated.

I see messages piling up on Discord where people have this issue. Epic needs to resolve this asap since most people don’t have > 1 acc and 99% of people will not think of using another acc to resolve this issue.

1 Like

hi all,

There was a similar problem a long time ago, and this was traced to the Epic Games Launcher, which controls all account activity on your account.

Recently found that some account data needed to be changed and found the Epic Launcher version was very old.

Removed the old EPGL version via Windows 10/11 uninstall function.

Restart your PC. IMPORTANT to flush all EPGL.

Download a new version.

Login using EMAIL/Password NOT all the other methods

Complete the Multi-Authentication method you have chosen to get your pass code.

Run verify on your Fortnite installation.

Log out of EPGL and restart your PC.

This time, log in to EPGL with your other account.

Complete the Multi-Authentication method you have chosen to get your pass code.

This time, your accounts should be able to see this update

This was only noticed when an annoying user had to be blocked, and on the other account, a fake user was blocked.

Every time you log in via EPGL, all your account details are updated.

When new features are added to Unreal Engine 5, they affect the account, but Fortnite/UEFN can use more than one account, which do not automatically get up dated.

All accounts used in Fortnite must be update/login from EPGL to get/sync account updates

Remember Unreal Revision Control will stop with error code 8 if you try to login twice using a secondary account!

see support articles

How to change the email on your Epic Games account - Account Support

Appreciate you Jimbo but as i mentioned above, that’s something I’ve already tried (Even if its indirectly)

This is also a Heartbeat issue under our accounts (Or at least under mine as I’ve seen in the logs)

Let me tell you all the things I’ve done so far to get this fixed:

  • Logged out then back in (No solution)

  • Logged out from my main, used a colleague’s account that can also publish and use UEFN, then back to my account (No resolve)

  • Logged into another account and successfully launched a session (This narrows the issue to my account)

  • Validated project “All projects are up to date”; after validation tried launching (No resolve)

  • Verified UEFN and Fortnite (No corrupted files)

  • Reinstalled Fortnite and UEFN (No solution)

  • Logged in on another machine and launched session (No solution)

  • Checked Verse (no errors reported)

  • Tried creating new maps/projects (Can’t even launch new projects)

  • DNS Flush (No resolve)

  • Restarted modem to also get a new MAC address (No solution, which btw tells us it’s not an internet issue because another account can launch with no issue UNDER the same MACHINE and INTERNET)

  • Tried using another ISP (Same issue; if it was a connection issue then another account shouldn’t be able to launch session with no issue)

  • Used phone USB hotspot to launch session (No resolve)

  • Changed LAN ports in modem (No resolve)

  • Changed Wi-Fi channels (No resolve)

  • Factory reset my computer (No resolve)

  • Changed my Epic Games email address

  • Changed my Epic Games username

  • Cleared UEFN local cache then launched session again (No resolve)

  • Created new islands with brand new different names (No resolve)

However, there was an instance where I was able to launch a session with no issue whatsoever:

  • By going back to the initial snapshot (on projects already created prior to this issue) or snapshots before I made ANY type of change, even if it was moving an object by 1.

  • In newly created projects, I still get the same “At least 1 module failed remote validation”.

Specific error logs:

LogValkyrie: FlowStep_ResolveSessionCandidates()
LogValkyrie: Error: FlowStep_ResolveSessionCandidates(): Candidate module [647dfbf5-4bef-e1e9-4d6a-9f82b8b6a01f] failed validation with error: [errors.com.epicgames.pre-processing.download_failure][]
LogValkyrieEditorAnalytics: Displaying Stats for Flow
LogValkyrieEditorAnalytics: =========================
LogValkyrieEditorAnalytics: Flow=Play
LogValkyrieEditorAnalytics: PlayFlow=15.228
LogValkyrieEditorAnalytics: ↳ PrepareProjectSourceData=3.927
LogValkyrieEditorAnalytics: ↳ UploadCookDownload=15.228
LogValkyrieEditorAnalytics: ↳ ValidationSessionInitializeContext=0.561
LogValkyrieEditorAnalytics: ↳ ValidationSessionRunLocalValidation=3.267
LogValkyrieEditorAnalytics: ↳ ProjectValidation=2.854
LogValkyrieEditorAnalytics: ↳ SyncWithContentService=0.323
LogValkyrieEditorAnalytics: ↳ UpdateProjectMetadata=0.142
LogValkyrieEditorAnalytics: ↳ InitSyncModules=1.091
LogValkyrieEditorAnalytics: ↳ StageProjectModules=0.153
LogValkyrieEditorAnalytics: ↳ GatherFilesForValidation=0.000
LogValkyrieEditorAnalytics: ↳ DownloadPublishedVerseFiles=0.092
LogValkyrieEditorAnalytics: ↳ ValidateProject=1.053
LogValkyrieEditorAnalytics: ↳ FindServer=6.569
LogValkyrieEditorAnalytics: ↳ MatchmakingToServer=4.549
LogValkyrieEditorAnalytics: ↳ ValidationSessionUploadCandidateSourceFiles=0.253
LogValkyrieEditorAnalytics: ↳ ValidationSessionCreateValidationSession=0.088
LogValkyrieEditorAnalytics: ↳ ValidationSessionCreateModuleVersions=10.862
LogValkyrieEditorAnalytics: ↳ ValidationSessionPruneScratchSpace=0.405
LogValkyrieEditorAnalytics: ↳ ValidationSessionResolveSessionCandidates=0.081
LogValkyrieEditorAnalytics: =================================

Thrax get them to vote and send what they’ve done to get it resolve if they actually got it resolve, I’ve tried everything under my power to get this resolved an nothing

hi @H6D6S, Thanks for your detailed response which will help Epic Support Engineer.

Forgot to say that used the 64 bit version with “Run As Administrator”.

On Windows 11 the installation of Fortnite/UEFN MUST use Run As Administrator for the first time.

Here is the error from Epic Support extract

To fix errors.com.epicgames.pre-processing.download_failure, run the Epic Games Launcher as an administrator, verify your system’s internet connection and check the Epic Games server status, and ensure your system meets the game’s minimum requirements. You may also need to close background applications that could interfere, verify the integrity of your game files, or reinstall the Epic Games Launcher.

Run as Administrator

  1. Close the Epic Games Launcher completely.

  2. Right-click the Epic Games Launcher shortcut.

  3. Select “Run as administrator” and try the download again.

Check for Issues

  1. Internet Connection: Confirm your internet connection is stable.

  2. Server Status: Check Epic Games Store to see if there are any server issues causing the problem.

  3. System Requirements: Make sure your computer meets the game’s system requirements.

Advanced Troubleshooting

  1. Close Background Applications: Exit any non-essential programs running in the background.

  2. Verify Game Files: If the error occurs during a game update, look for an option within the launcher to verify the game files’ integrity.

  3. Reinstall Launcher: As a last resort, you may need to uninstall and reinstall the Epic Games Launcher.

That didn’t work :frowning:

Is this still happening after the last update?

We are a two-creator team and we have the same issue. It appeared after the last update (yesterday morning to be precise) and we have the same logs as @thrax207.

Yes still happening @Flak . Got a new variant of the issue now:

LogValkyrie: Error: FlowStep_UploadCandidateSourceFiles(): Failed to register session candidates: [Failed to upload sources for module StealABrainrot: Error=[Failed to fetch scratch links]]
LogValkyrieEditorAnalytics: Displaying Stats for Flow
LogValkyrieEditorAnalytics: =========================
LogValkyrieEditorAnalytics: Flow=Play
LogValkyrieEditorAnalytics: PlayFlow=200.983
LogValkyrieEditorAnalytics: ↳ PrepareProjectSourceData=61.475
LogValkyrieEditorAnalytics: ↳ UploadCookDownload=200.983
LogValkyrieEditorAnalytics: ↳ ValidationSessionInitializeContext=2.382
LogValkyrieEditorAnalytics: ↳ ValidationSessionRunLocalValidation=59.029
LogValkyrieEditorAnalytics: ↳ ProjectValidation=56.764
LogValkyrieEditorAnalytics: ↳ SyncWithContentService=1.714
LogValkyrieEditorAnalytics: ↳ UpdateProjectMetadata=0.999
LogValkyrieEditorAnalytics: ↳ InitSyncModules=26.154
LogValkyrieEditorAnalytics: ↳ StageProjectModules=2.445
LogValkyrieEditorAnalytics: ↳ GatherFilesForValidation=0.013
LogValkyrieEditorAnalytics: ↳ DownloadPublishedVerseFiles=0.658
LogValkyrieEditorAnalytics: ↳ ValidateProject=24.755
LogValkyrieEditorAnalytics: ↳ FindServer=11.720
LogValkyrieEditorAnalytics: ↳ MatchmakingToServer=7.520
LogValkyrieEditorAnalytics: ↳ ValidationSessionUploadCandidateSourceFiles=139.492
LogValkyrieEditorAnalytics: =================================
LogSlate: Window ‘Unable to Play’ being destroyed
Message dialog closed, result: Ok, title: Unable to Play, text: Failed to upload source files

Just an update on above, that was an unrelated random error I received.

No idea why or how that came up, can’t reproduce it.

I can confirm with my same account that it’s NOT fixed:

LogValkyrie: Error: FlowStep_ResolveSessionCandidates(): Candidate module [a4c5b261-4cc7-9082-bfa1-70a7a5394581] failed validation with error: [errors.com.epicgames.pre-processing.download_failure]

Still same error.

When I switch to another acc, everything works fine.

Started happening to me after yesterday’s update

@D4G_fnc @ZeroValk94 @H6D6S

Do you remember first time this started happening something out of the ordinary?

For me; I was launching a session, but then I did not want that session to launch since needed to 1 more change. I cancelled it, of course that took unbelievable long, so I killed UEFN with task manager.

After that the issue appeared for me.

Thank you, I let the team know.