Downgrade unreal engine 5 project to 4.27 or 4.26

Hello , I’m trying to downgrade my UE5 project to a older version 4.27 or 4.26.

i have done the following.

  1. go to Epic games launcher and clone the project
  2. go to the clone folder and select the project and right click and select ‘‘switch unreal engine version’’ I have done this in 4.26 and 4.27.
  3. the project is opening in the old versions but is missing the map, on the folder i can see the map but not in the editor.

4.i drag and drop the map in the editor but i had the following error ‘’ unknown extension umap’’

I am not sure why it does that , any help is appreciated

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Downgrading is not possible.

Did you finally work out? Same Situation here,help plz~ :sweat_smile:

The typical limitation of UE. They, at least, should allow the engine to ‘try’ to open it; things without internal changes should work really fine! Only those with new functionalities could not work, but that should be OUR problem, not being automatically fully locked, without the freedom to make the try… I already suggested it, but it seems nobody cares.


you can downgrading the procjet just click in .uproject and “switch unreal version”


The button only works upwards. :smiley:

Yeah since they changed the physics engine i don’t think you can revert back versions only convert in place to a higher version, if converting in place certain blueprints may not function like the previous version so you may have to fix them in particular circumstances, others will convert fine simple props or environments convert fine but anything with physics like motion to cars or other animations may break during conversion, best thing you can do is always keep an old version separate as backup in case you need to revert, but no you can’t start a project in 5 then go backwards in versions with the same project.

oh wow amazing you were so helpful we didn’t know that and nothing said that that didn’t work

Sucks that you can’t downgrade. I mean, makes sense with Nanite not being supported… but considering the fact that V-Ray only works in 4.27 it just… sucks. Does anyone know of a vray work around for 5.1?

I made a plugin ( that downgrades assets to 4.27, with certain limitations (for now). Let me know if it works for you. If not, contact me and I can do more research/fix it.

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