**CRITICAL**- Can't launch UEFN session after v36.00 - verse code Validation Fails, pointing to sys/published outdated code

[BushyBrowse]

Summary

After v36.00, UEFN has an issue with generating the proper updated code from our files to our Project’s ‘…/Plugins/…/sys/’ folder. Causing validation to fail - leaving the project broken. (Cannot launch a session, meaning cannot publish, playtest or update my island)

This is a complete work stoppage. This is critical as us developers face deadlines.

I really need this fixed ASAP.

Please select what you are reporting on:

Unreal Editor for Fortnite

What Type of Bug are you experiencing?

Verse

Steps to Reproduce

Not exactly sure how to reproduce the error but

1. Have a project from pre v36.00
2. Try to launch a session
3. Witness a Validation error about code in your .verse file
4. Attempt to fix the code
5. Code builds successfully
6. Try launching a session again
7. Validation Errors arise again
8. Search for the file that Verse Diagnostics points to
9. See that it is referencing a .verse file from a folder path that doesn’t exist in the your file explorer
   (/…/Plugins/…/sys/published/Content/)
10. See a related folder path
    (/…/Plugins/…/sys/versions/1400/Content/… .verse)
11. Open the verse file
12. Fix the code the validation error is pointing to
13. Save
14. Re-Validate project
15. More unrelated compile errors show now
16. Hit the forums

Expected Result

If VSCode has no compile errors, Then I should be able to launch a session.
This was 100% confirmed to be working before the v36.00 update. I work on my project every day. Even my backups face this same exact issue.

Observed Result

(I cannot go into TOO much detail as I am working on a very sensitive project)

1. I first got an error when opening up my project regarding an asset being used during ‘SetMesh’ for an editable creative_prop

2. I deleted those lines of code and anything related to that editable creative_prop (only a few lines) and recompiled

3. Everything is fine - it builds successfully.

4. Then when I try to launch a session, it runs through validation, but fails again.

5. In the Verse Diagnostics, it tells me the same exact reasons about the mesh code even though the code doesn’t appear to exist in my .verse files anymore (since I removed the code) and it compiles no problem.
   Verse Diagnostics is actually pointing to a compilation error in a seemingly generated verse file but in a different location than the original .verse file. This OTHER location is at ‘/…/Plugins/…/sys/published/Content/… .verse’ (Never seen it before)
   But this folder does NOT exist in my file explorer (+ with Hidden items shown)
   So I cannot edit them.

6. However, I looked around and found a similar path that DOES exist in my project that contained the verse file in question: ‘/…/Plugins/…/sys/versions/1400/Content/… .verse’

7. I opened the file in a text editor, removed the code (just like I did in step 2 from my regular .verse file) and recompiled

8. NEW Validation errors showed up regarding other lines of code instead of just the one error previously. But they all seem like random errors over 60+. Most of them claiming that a specific variable doesn’t exist in a class. But after inspecting, that claim is false. This is where I’m stuck at.. No matter what I do here, it just won’t validate.

9. I even tried deleting all the files from the location that seemed to be generating the outdated verse files (…sys/versions/1400/Content) and relaunched UEFN, but the files regenerated and gave me the same exact validation issue about the code I already got rid of

10. What I’ve observed is that the file path that the Verse Diagnostics are pointing to (/…/Plugins/…/sys/published/Content/) does not generate new and correct updated code to validate after we’ve made changes + compiled the code again in our standard files from our ordinary project file’s verse paths.

11. Verse Diagnostics seems to point to sys/published/Content, when in the Windows file explorer, we can only see and edit the verse files inside of sys/versions/1400/Content. And even after doing so, it still doesn’t clear out errors properly. Seems like the files here are not pulling correct data when UEFN has to perform ‘LogValkyrieSyncProject: Display: Profile Begin SyncProject.DownloadPublishedVerseFiles’. Or somewhere during ‘LogValkyrieSyncProject’

Platform(s)

windows

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Additional Notes

• I’ve verified and relaunched UEFN
• I even deleted the generated files at …/Plugins/…/sys/versions/1400/Content/
  since it would regenerate them again but still ran into the same issue and the regenerated files had the same lines of code that were failing validation. Maybe it’s pulling this outdated code from somewhere on the cloud?
• I don’t use URC (Manual Backup methods)
• I don’t use OneDrive
• I even tried this on my other PC and still the same exact issue

[nicoplv]

Hello,

This looks similar to the issue discussed here: : Validation error from outdated files in sys/versions (regression?)

Unfortunately, there is currently no solution available to launch a session. I hope it gets fixed soon!

In your UEFN project, what is the number of the latest version shown in the project size window?
In my case, the version number there is higher than the one generated in the sys folder. I was thinking that might be the issue.

[13HARAMBE37]

delete verse files in Documents\Fortnite Projects\projectname\Plugins\projectname\sys\versions\769\Content

then remember to push changes and reopen project

it didnt work first for me so i reverted last snapshot before trying anything with verse fixes, but i guess if u dont use urc then i dont know

[BushyBrowse]

Actually I just found that this resolved my issue! 100%

Steps to resolve:

1. Close UEFN completely (Until it says ‘Launch’ in the Epic Games launcher again)
2. BACK UP YOUR PROJECT MANUALLY. URC + MANUAL BACKUP FILE.. PLEASE!!
3. Go to the file location of your ‘.uefnproject’ file
4. Open the .uefnproject file in VSCode
5. Add the scenegraph section exactly how it looks from this post:
   (Clarification: DO NOT REMOVE ANY TEXT, you’re just adding the section in the red square)
   [MAJOR] Asset Reflection - #29 by Kiriousaurus
   
   
6. Next, go to your 'projectname/plugins/projectname/ folder
7. open the .uplugin file in VSCode
8. Add
   "EnableSceneGraph": false
   
   

Upvote this forum post and this response and the other post so people can benefit from this!

[nicoplv]

Thank you, it looks like it works partially. I get an other error message now , but the launch process went a bit further this time.

I’ve seen other posts on the forum where people are getting the same error.

Thanks again, and I’m glad to hear you found a solution for your project!

[Bug-Reporter]

FORT-920717 has been created and its status is ‘Unconfirmed’. This is now in a queue to be reproduced and confirmed.

[Flak]

Closing as duplicate.