UE5 doesn't allow the opening of any assets or levels made in UE 4.27

So I’ve been working on a map in 4.27 for a few weeks now and in 4.26 before that. I decided to try opening it in UE5 Early Access 2, but can’t open any assets or levels. It is not even that it says they are incompatible. They just don’t appear in the content browser, but they do appear in file explorer. I even tried importing a variety of different things using the merge tool in 4.27 but none of this stuff appears in UE5. Assets from 4.26 do appear however. Is there a fix to this at all?

They officially said that 4.27 will not be compatible with UE5 EA, but it will be with UE 5 when it comes out

Ah ok thanks, never saw that.

Please. let me know if you find a solution, I have the same problem.

Hi,
It seems to come from the version of the engine that the map was saved on.
Since the latest 4.27 is a newer engine version in date compared to ue5 early access release.
So the project thinks the map itself is saved on a higher version number.
Try to migrate or transfer the map to an older version of 4.27 or 4.26 and save it. Then migrate it
from there to ue5. It should work then. :slight_smile:

I couldn’t migrate backwards. But I opened the 4.27 map and a new map in 4.26 and used copy/paste to get most assets across to the older version. If someone runs into the same problem.

I tried the copy/paste but isnt working for me.

Unreal 5 hasn’t got the clip board feature so you need to use Unreal 4.26 and then migrate it to Unreal 5.

Use CTRL+C to copy and the CTRL+V to paste. All assets need to be in the project and you need to be able to open them and place them into a new level. If they are saved with the higher version they might not be usable.
Select a level in the level browser, right click on it and choose Select Actors from the menu. Press CTRL+C and then copy it into notepad. It should read like this

Map
Begin Level
Begin Actor Class=/Script/Engine.StaticMeshActor Name=P_InfiniteRS540_5 Archetype=/Script/Engine.StaticMeshActor’/Script/Engine.Default__StaticMeshActor’
Begin Object Class=/Script/Engine.StaticMeshComponent Name=“StaticMeshComponent0” Archetype=StaticMeshComponent’/Script/Engine.Default__StaticMeshActor:StaticMeshComponent0’
End Object
Begin Object Name=“StaticMeshComponent0”
StaticMesh=StaticMesh’"/Game/ArchVizUI_V3/Assets/Appliances/Kitchen/SM_InfiniteRS540.SM_InfiniteRS540"’
StaticMeshImportVersion=1
StreamingTextureData(0)=(PackedRelativeBox=4294901760,TexelFactor=4.185697)
StreamingTextureData(1)=(PackedRelativeBox=4294901760,TextureLevelIndex=1,TexelFactor=33.485573)
StreamingTextureData(2)=(PackedRelativeBox=4294901760,TextureLevelIndex=2,TexelFactor=41.856968)
StreamingTextureData(3)=(PackedRelativeBox=4294901760,TextureLevelIndex=3,TexelFactor=412.130157)
StreamingTextureData(4)=(PackedRelativeBox=4294901760,TextureLevelIndex=4,TexelFactor=167.427872)
StreamingTextureData(5)=(PackedRelativeBox=4294901760,TextureLevelIndex=5,TexelFactor=167.427872)
StaticMeshDerivedDataKey=“STATICMESH_8A752B9E4A904F25B0AB9D65A70A8BDC_228332BAE0224DD294E232B87D83948F1$2e0_DepthOnlyIB_ReversedIB_2FFD3DCCD4BB75B44CD05C183809FEE550000000001000000010000000100000001000000010000000000000000000000000000004000000000000000010000000000803F0000803F0000803F0000803F00000000050000004E6F6E65000000803F0000000000000041000000000000A042030303000000000”
MaterialStreamingRelativeBoxes(0)=4294901760
VisibilityId=55
RelativeLocation=(X=555.000000,Y=-65.000000,Z=90.000000)
RelativeRotation=(Pitch=0.000000,Yaw=180.000244,Roll=0.000000)
CustomProperties
End Object
StaticMeshComponent=“StaticMeshComponent0”
RootComponent=“StaticMeshComponent0”
ActorLabel=“P_InfiniteRS540”
End Actor
Begin Actor Class=/Script/Engine.StaticMeshActor Name=P_GenShowerRail4 Archetype=/Script/Engine.StaticMeshActor’/Script/Engine.Default__StaticMeshActor’

You can then copy this into the new level of the older version.