Drag an drop material to object ID not working anymore

I need help !

I am working on an architectural visualisation projet that we need to send to the client tomorrow and this functionality not working is becoming a nightmare.

Usually when working on an object having multiple ID (for example walls inside a house) I just have to drag and drop the material on the part (ID) I want it to be applied to in the viewport. Now it doesn’t work anymore. When I do it it is applied to a random ID not related to the one I had in front of me.

What am I missing ? Is this a bug or did I turn off something by accident ?

Ok so here’s what is going on.
My imported meshes are coming from 3ds max and are fbx’s.
Apparently when imported to Unreal the elements (material) do not match the lod sections.

Please help. We can’t work like this and I can’t go back to the previous version of Unreal.

Hi, would you mind sharing one of your meshes that has this problem. Some of these import issues should have been fixed already so there must be something about your mesh that is still causing the issue to occur.

If you are worried about privacy you can PM me on the forums, here is a link: https://forums.unrealengine.com/member.php?484739-Ed-Burgess

I can also tell you that we are not the only one concerned by this issue. One scene made by one of our freelancers also has ID’s completely randomised.
Here’s one mesh with multiple ID’s concerned by the problem

To anyone having this issue. We have developed a plugin able to fix the discrepancy between LOD sections and ID’s. It works on both the actors in the scene and the source assets and it preserves the materials already assigned on the wrong ID’s.
While Epic fixes the issue you can contact me if you are in need of the plugin to fix an already corrupted project.

I also reported this issue a while ago on the forums here:

Hi mannyLectro,

I have reproduced your issue in 4.14.3 however, it seems that the issue has already been resolved. I tested this in the 4.15 preview. Try testing this on your end and you will find that this should be working again.

If you are still getting errors just leave a comment here and we can continue the investigation.

Thank you for making this post and happy developing!


Hey Ed,

I’m getting this issue as well. Also have some quick archvis to get out. Do you recommend using the 4.15 preview? Is it stable? Will I possibly run into other bugs? Or would it be better to run 4.13?


It is very possible you will run into additional bugs on the preview. For production or development it is always best to stick back to a more stable version (4.13) rather than go forward.

I merely suggested the OP try to test on 4.15 to confirm the issue is fixed on their end. That way making a bug report is pointless if the issue is already resolved.

I would never suggest developing on a preview build or a new engine release.If you do plan to migrate, do so with caution and expect bugs or issues. You may not run into any, but it is better to be prepared with back ups or copies.

I hope that answers your question.

Here’s the plugin : GitHub - etbh/RepairMeshSectionMismatch2: This Unreal Engine Plugin repairs the mismatch between LOD Sections and Element IDs in Meshes for 3DSmax FBX files imported in 4.14