Symptoms
- “Invalid or duplicated SKU”
- Variable products import without their variations
- Variations appear as separate products
- Repeated imports create duplicate variations
Common causes
- The same SKU exists elsewhere in the file or store
- A variation points to the wrong Parent SKU or ID
- Parent and variation rows use inconsistent identifiers
- An update changes the identifier WooCommerce uses to match an existing product
How to check
- Find blank and duplicate SKUs inside the CSV
- Confirm every variation Parent value resolves to one variable product
- Confirm Type is variable for parents and variation for children
- Review whether the import is intended to create or update products
How to fix
- Give every variation a unique SKU
- Restore an exact Parent SKU or supported Parent ID
- Import parent rows before dependent variations when separating files
- Back up the store and verify update settings before overwriting
Prevention
- Use stable identifiers across exports and updates
- Keep a parent-to-variation mapping check in the preparation workflow
- Test a small representative file before a full catalog import
Evidence and scope
This page passed TinkerVane's Evidence Gate: a documented real problem, clear search intent, a matching file-level capability, a duplicate-content check, and an explicit overclaim boundary.