[Issue] UE4 conversion to UE5 - A single .umap is not upgraded

Hey guys, I’ve been trying multiple times to upgrade a UE4.27 project to UE5 and its working like 99%.

The exception being a single level that does not want to show up in UE5. I haven’t seen any errors appear about an issue on upgrading my project.

Any ideas on what I could do, to debug this further?

Sounds confusing but you can’t upgrade a 4.27 project to 5 only up to 4.26. I made this same mistake.

It’s not really confusing. UE5 was branched off somewhere around 4.26, so 4.27 and UE5 are now diverging paths with different migrations etc. They’re planning to have UE5 compatible with 4.27 on release.

Oh, I didn’t actually know that! Thank you for the clarification Vexar & Zeblote!

@Vexar & @Zeblote - Since I know now that 4.27 cannot be upgraded (Even though the Project I tested with does seem to upgrade most of the way, for some reason) to UE5 at this time. I’ll give a bit more context to what I was doing, that I think is worth mentioning now.

(1) When I first started on my project. I created 4.26 (in Windows) and everything was working as normal.
(2) I recently went on a trip and brought my Mac Laptop around to create a new project in 4.27, to do some Level Design. (This is the level that I pointed out that wouldn’t work in my UE5 project)
(3) After I returned, I wanted to migrate my 4.27 Level into my 4.26 project and learned that Maps were not cross-compatible and the way to address this. Was to upgrade my 4.26 project to 4.27 and then migrate my Level from my Mac to my newly upgraded project to combine the two.
(4) Everything seemed to be working fine in my upgraded 4.27 project.
(5) I thought I’d give upgrading my combined 4.27 project to UE5 a try and noticed that the one specific level that I wanted to use. Did not seem to be working.

The odd thing, is that I have other Levels that were originally created in 4.26, later upgraded to 4.27 that seem to be working in my UE5 upgrade.
I know UE5 is heavily under development, so their are bugs to be expected and I can’t speculate to why it failed. But it was still interesting, nonetheless. :slight_smile:

Could be that a level created 4.27 contains meta data that is filtered by UE5, and that the 4.26 version didn’t get that data, if you converted your project over to .27 and opened every level then tried to convert the project to UE5 you could test to see if this is true then you know the only difference between the data is opening it and saving it in 4.27.

Regardless of the outcome we just have to wait if we moved to 4.27 to convert over to 5. Which is fine I just need a stable build to make progress at this point.

i have this issue aswell, i have my whole game project working great in UE5EA2, meta humans and all, i bought them some armour

the entire pack migrates to UE5 perfect bar the one part i want aka the metahuman versions of the armour as it was saved in 4.27

only fix is to export to fbx from ue4.27 then re import and fix the cloth in UE5, would be nice if their was a way to update the ue version in uasset files, i get why from above and for stuff like blueprints it makes sense, however for a skeletal mesh to embed the version is odd

best i have found is edit the hex from 4.27 to 4.26.2

seems dangerous to me

if the engine was built from source using the current branch, would this still be an issue?