Oh, now I get why your materials are getting renamed by Blender by adding a number to them.

Oh Oh.....oh no.
Looks like that' might not be my problem then. I always shut down Blender and re-load it when I import a new FBX character to start a new project.
Actually, part of my investigations over what is wrong I couldn't find any textures or materials anywhere in Blender. But I only did a quick search so far.
I will look into it more tonight

i7-3770 3.4GHz CPU 16 GB Ram   
GeForce GTX1080 TI 11GB
Windows 10 Pro 64bit

I think Kellytoons suggestions is what the problem I am having is. Either I am not ticking the settings correctly when I import the FBX file or its relating to my version of Blender.

i7-3770 3.4GHz CPU 16 GB Ram   
GeForce GTX1080 TI 11GB
Windows 10 Pro 64bit

Come to think of it, that is where you would see the bone names. To see the materials easily, click on the little shaded sphere icon at the top of the modify panel.

Hooray, I have it partially fixed now. Just need to do a bit more work to get the textures back onto the character but at least I can now load the character I am working on into CC3. I want to thank Kellytoons and Rampa because their comments helped me to discover how to fix the problem on the characters I have been working on. I still need to fix the import of the CC3 character FBX into Blender so it doesn't loose the materials. I suspect updating Blender is going to fix that and I will confirm it once I do that. I was worried about having to redo the things I have been working on but I found how to correct it.
Posting here what I did in case it helps anyone else who might also have this problem? Though, maybe it is just my own problem due to the way I work.

Here is one of my first CC2 content projects. It shows some of the Materials Names on the right (Skin_Body, Skin_Head etc etc). So importing CC2 FBX exports into this version of Blender I am using had no problem bringing in the Materials.



Here is a CC3 FBX export I brought into this same version of Blender. It shows there are no Materials loaded into Blender so when I modified the character and exported him as FBX there were no materials in the export and that's why I got the errors I showed when I tried to import it into CC3. It only does this error when I try to import the FBX exported from Blender. I can import the original FBX file I exported from CC3 back into CC3 so its not CC3 that looses the material in the FBX it exports. Its Blender that is loosing the materials when It imports the CC3's exported FBX. Need to figure this out why but thinking if I update Blender this issue will disappear. I hope.


Here is the UV mapping of the CC2 character imported with the FBX file into blender


And here is the CC3 FBX files UV mapping imported into blender. So all that is correct, they are differently structured but they both get imported fine.


So what I did to fix the problem importing the Blender export FBX was manually create all the materials and name them as they are named in CC3.
Here is a partial display of them in Blender, notice they are named differently to how they were named in CC2.
Once I created the Materials I went into edit mode, selected one of faces in the UV map of the faces that apply to each Material. Kept the mouse in the UV map and pressed Ctrl-L to select all the faces connected to the one I selected. Then I went back t the Material and assigned the selected faces to that Material. Repeat that for all Materials created.


And here is the Blender modified character imported back into CC3 successfully. This image also shows the names of the Materials which I used to name the Materials I created in Blender.


All I need to do now is load the textures back into those Materials.
And finally, find out how to stop Blender loosing them when I import an FBX file for future contents I make




i7-3770 3.4GHz CPU 16 GB Ram   
GeForce GTX1080 TI 11GB
Windows 10 Pro 64bit

When you exported the FBX from CC3 did you embed the textures?  I did that, and they were fine when they came into Blender (again, you will lose roughness/normal maps, but that's par for the FBX course).

Blender shouldn't lose any textures or mapping (and didn't when I tried it).  It loads whatever is in the FBX file.

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Alienware Aurora R16, Win 11, i9-149000KF, 3.20GHz CPU, 64GB RAM, RTX 4090 (24GB), Samsung 870 Pro 8TB, Gen3 MVNe M-2 SSD, 4TBx2, 39" Alienware Widescreen Monitor
Mike "ex-genius" Kelley

Yes definitely embedded the textures when I exported the FBX file from CC3.
Just to confirm it I just tried exporting it again with the embedded textures checked and imported it into Blender and it had no textures still.
Also tried unticking the rotation option as you suggested when importing it into Blender. Still no Materials when loaded into Blender


i7-3770 3.4GHz CPU 16 GB Ram   
GeForce GTX1080 TI 11GB
Windows 10 Pro 64bit

The recent 2.8 builds have FBX import/export implemented. It seems to be easier to deal with materials, as they show up on the model with no special set up. Makes it nicer to work with.

OK, I just updated Blender to version 2.79, imported the CC3 FBX file that I exported before and was loading into Blender 2.78 without the materials.
It is now loading into 2.79 with the materials. I then exported the FBX file from this new Blender version and imported it into CC3 successfully.



i7-3770 3.4GHz CPU 16 GB Ram   
GeForce GTX1080 TI 11GB
Windows 10 Pro 64bit

If someone could do a quick video getting this to work that would be fantastic.  I need to export my character with hair so i can tweak a few settings to help with skin weights. And being the fbx back into cc3.