Avatars · VRM — deeper
When your avatar needs a little surgery.
An import-error reference and a full worked example for avatars that need an authoring pass.
VRM 0.x and VRM 1.0 normally import without conversion. Reach for this page only when the importer reports a separate problem.
import-error reference
When import fails — what it means, what to change.
Quick checks that prevent most failures. Don't rename a file to "convert" it (e.g. .gltf→.vrm) — export with the right exporter. Prefer .glb (it embeds buffers + textures). Re-export from the original scene rather than hand-editing. If you ran an optimizer, try exporting without optimizations first.
File type / format not recognised
"This file type isn't recognized." · "Unsupported version." · "Unknown / Legacy glTF." — the importer can't read the file as a supported format/version. Fix: re-export VRM as a VRM 0.x or VRM 1.0 .vrm, glTF as 2.0 (prefer GLB), or FBX with a different Binary / ASCII or version preset. Run a clean pipeline with no optimizers.
VRM version & VRMC_vrm metadata
"…failed validation: Missing specVersion / meta / meta.name / humanoid." — a file exported as VRM 1.0 has an incomplete VRMC_vrm block. Fix: export it from a VRM 1.0 exporter with a valid specVersion, a meta block (at least a name), and a humanoid definition that validates. VRM 0.x uses different metadata and is supported directly.
Humanoid mapping & rig hierarchy
"Some required humanoid bones aren't mapped." · "Parent mismatch for {Bone}…" · "…has a parent that doesn't exist." — the humanoid mapping and the actual bone parenting disagree. Fix (Blender): verify each bone's parent in Edit Mode, map every required humanoid bone to a real bone, ensure mapped bones' parents are also mapped, and don't map humanoid bones to non-humanoid helper bones. Re-export without changing the avatar's VRM version.
Import limits exceeded
Too many material slots · bones · mesh primitives · triangles · vertices · indices. Fix: merge materials (atlas/bake), enable "Only Deform Bones," join meshes that share materials, decimate/retopologise to cut polygons, or split the asset into multiple meshes to stay under each limit.
Unsupported glTF extensions & compression
"…requires extensions MEs doesn't support." · "…uses meshopt compression, which isn't supported." Fix: re-export with those extensions disabled, bake special features into core materials/textures, and turn off meshopt / mesh compression — export a plain GLB.
Structural & parse failures
"No mesh geometry to import." · "Buffer view… has no buffer." · "Invalid JSON / Invalid glTF." · FBX: "Truncated file / Invalid UTF-8 / Unsupported version." — malformed or inconsistent content, usually from manual edits or aggressive optimization. Fix: re-export a fresh GLB from your DCC with no post-processing; confirm meshes (and, for skeletal meshes, skin weights/joints) are actually included; never hand-edit the file.
a worked example
Upload LAPWING into MEs
The whole pipeline on a real avatar — preparing the BOOTH model LAPWING in Blender and bringing it in as VRM 1.0.
Requires Blender with the VRM add-on installed and enabled before you start.
- 1
Prepare textures
Convert all texture files PSD → PNG — smaller, and it avoids import issues.
- 2
Import the LAPWING FBX into Blender
Load the base model.
- 3
(Optional) Remove the Bolero / Cape
Remove this outfit if you do not plan to use it. Ignore the hands for now — they're hidden inside the cape and return to normal once the shape keys are removed.
- 4
Join meshes
In Shading, select all mesh objects → Object → Join for cleaner material handling.
- 5
Delete unused shape keys
Open Shape Keys and delete them all — this restores the hands and cuts file size. Keep only expression shape keys you actually need (set Value 0 → 1 to preview).
- 6
Assign materials & textures
For the body: select LapBody.004, add an Image Texture (Shift+A), connect its Color → Base Color, and Open LapwingBody.png. Optionally add Emission at 0.2. Repeat for the rest:
Material → texture Material Texture (PNG) LapEye.004 LapwingBody.png LapHair.004 LapwingHair.png LapShoesBag.004 LapBagShoes.png LapClothes.004 LapwingClothes.png LapwingUnderwear.004 LapUnder.png LapShadow.004 base color + Emission 0.1 - 7
Confirm VRM 1.0
Make sure the file is set to VRM 1.0.
- 8
Export & re-import
Export as VRM 1.0, re-import into Blender, export again as VRM 1.0. This double-pass prevents "noodle arms."
- 9
Import into MEs
Open MEs, upload the final VRM, and start using LAPWING. 🎉