Asset Upload Failed: “An error occurred during the file processing” for Blender / Alembic files

[Yaratici_Etkiler]

Summary

Hello friends,

I’m encountering a processing error while uploading my 3D asset pack to Fab. During the automated ingestion/processing step, the upload fails with the following message:

“An error occurred during the file processing”.

Here are the technical details of my package:

Primary Software: Blender (along with Cinema 4D cache files)

File Formats Included: .blend, .abc (Alembic), .fbx

Package Structure: Standard .zip archive containing the .blend file, textures directory, and cached Alembic animation data.

Things I have already verified:

Zip archive integrity is solid (no corrupt files, standard zip compression).

File and folder paths do not contain special characters, spaces, or non-ASCII characters.

Relative paths are set.

I tested it in Chrome, Firefox, and Edge browsers. I also tried it with Blender versions up to 4.x LTS. I didn’t get any results.

Has anyone run into this specific processing error recently? Does Fab’s automated parser have specific constraints regarding Alembic cache sizes, Blender Asset Browser metadata, or archive root directory hierarchies?

I have also tested the project using Blender 5.0, Blender 4.5.

I imported the project files into Blender 4.5 and exported them as a .blend file. However, when I attempt to upload this file to the Blender section of my product listing, I continue to receive the error message: “An error occurred during the file processing.”

I would like to include Blender files in my listing, but this issue is preventing me from proceeding. Any guidance or workarounds from the community or Epic staff would be greatly appreciated.Could you please assist me in resolving this?

Thank you…

Please select what you are reporting on:

Creative

What Type of Bug are you experiencing?

Assets

Steps to Reproduce

1. Create a product listing on Fab and select the Blender file type.

2. Upload Wind_Blown_Debris_Pack_Anim_01.blend.

3. The file uploads, but Fab displays “An error occurred during the file processing” while extracting the technical details.

4. The same error occurs when uploading the uncompressed copy of the file.

Expected Result

Fab should process the uploaded .blend file successfully and extract its technical details for the product listing.

Observed Result

Fab uploads the .blend file but fails while extracting its technical details and displays: “An error occurred during the file processing.” The same error occurs with the uncompressed copy.

Platform(s)

Windows 11

Upload an image

Video

blender_error_video.mp4

Additional Notes

The file was saved without compression and is in Blender 4.5 format. I also tested a basic other Blender file, which processed successfully. Could you please check whether this error is related to specific data or features in my file? I can provide the file for further investigation if needed.

[Jimbohalo10]

hi @Yaratici_Etkiler

Well Epic Developer AI found this

Here is the direct, step-by-step workflow to bake procedural nodes or complex material networks into flat PBR textures using Blender’s Cycles engine.

Step-by-Step Texture Baking Checklist

1. Switch to Cycles Engine
   • Go to the Render Properties tab (camera icon).
   • Change the Render Engine from Eevee to Cycles (baking is only supported in Cycles).
2. Unwrap Your Mesh (UV Mapping)
   • Switch to the UV Editing workspace.
   • Select your object, go into Edit Mode (Tab), press A to select all geometry.
   • Press U and choose Smart UV Project (or unwrap manually with seams). Ensure no UV islands overlap.
3. Set Up the Target Image Node
   • Switch to the Shading workspace.
   • Select your object and look at your material node tree.
   • Press Shift + A and search for an Image Texture node. Put it in an empty space (do not connect it to anything yet).
   • Click New on that node. Name it (e.g., Asset_BaseColor), set your resolution (e.g., 2048 x 2048 or 4096 x 4096), and click OK.
   • Crucial: Keep this Image Texture node selected (it will have a white highlight outline). This tells Blender where to bake the data.
4. Configure the Bake Settings
   • Go back to the Render Properties tab and scroll down to the Bake section.
   • Under Bake Type, select the map you want to output first (e.g., Diffuse or Emit).
   • If baking Diffuse: Under the Influence sub-section, uncheck Direct and Indirect. Leave only Color checked. This ensures you bake just the raw surface color without burning your scene lights/shadows into the map.
5. Execute the Bake
   • Click the Bake button at the top of the Bake section. A progress bar will appear at the bottom of the screen.
   • Once finished, open your Image Editor panel, look for the image you named, click Image > Save As, and save it into your flat root folder as a PNG or Targa.
6. Repeat for Other Maps
   • Create a new Image Texture node for your next map (e.g., Asset_Roughness). Keep it selected.
   • Change the Bake Type in the Render Properties to Roughness.
   • Click Bake, then save the resulting image.
   • Repeat this process with the Bake Type set to Normal (ensure your Normal Space is set to Tangent).

Connecting the Baked Textures

Once all maps are saved, disconnect your complex procedural node setup from your Principled BSDF shader. Plug your newly baked flat texture files (BaseColor, Roughness, Normal) back into their corresponding Principled BSDF inputs. Your model will now look identical, but it is 100% ready for the Fab Store validation process.

According to EDA this maybe where failure for Fab Store validation process occurs

[Yaratici_Etkiler]

Thank you for your prompt response.

I will test everything you’ve outlined and let you know the results here.

Thanks again.