FBX re-import not updating UVs?

This is a follow up to a thread I posted on the forums (link text). Basically re-importing geometry from an FBX file is not updating the UV channels. See this video for a demonstration of what is happening - link text

The only workaround I have right now is to delete the object from the project entirely and import from fresh, which is not ideal.


Hello MClemenston,

Pleas make a copy of your project before trying this

If you delete your Intermediate, Saved, and Derived Data Cache from your main project folder this will force your project to recompile.

This will clear up any information that is left over from the first time you imported your .fbx. Effectively, this should allow for your .fbx to update and keep updating every time that you re-import.

These files are located in Unreal Projects > " Project Name " > and they will be within this first folder.

I am having the same issue, but unfortunately these steps didn’t work for me. Using UE 4.14.

same issue here in 4.14.3 re-import and even deleting the object does not update the second UV’s (lightmap UV’s) … 1st uv’s ARE updated.
Deleted Intermediate and Saved dirs

The problem still persists with 4.15.1
Deleted the asset from the project and the Intermediate+Saved dir. Restarted the project and imported the file again but still the same UVs as before.

Ok, in my case the issue was caused by exporting to FBX with Opensubdiv modifiers on the asset.

Unchecking the subdiv export settings fixed the issue.

The bug is still there, very annoying.

But I’ve found a workaround:
1- open the static mesh.
2- click the SourceFile button ("…") and click open.
3- in the menu click Asset > Reimport.

I’m having the same issue and it’s driving me crazy, anyone find a solution?

I had this same issue, but it’s because I still had “generate lightmap UVs” checked, so on re-import it was just reinterpreting my primary UV map. Once I took that off, both maps are fine.

Hi everyone,

I was stuck on this one and in my case it was a different solution than all the above.
So I thought I’d share it here in case someone else falls prey.

In C4D you can have a UV map for the geo, but the applied material be on another type of projection that is not UVW.

When you import the FBX to UE, it will read the projection on the material instead of the UVW. Hence the confusion.

Long story short, set all material projections to UVW.

best of luck to everyone.