If you're unable to search for a SKU on the Restock Inventory page or the app is not syncing a particular SKU, the issue is usually caused by an invalid SKU format.
Why Does This Happen?
Duplicate SKU Sync relies on Shopify APIs to search and synchronize products by SKU.
Shopify does not reliably support SKUs that contain spaces or special characters, which can prevent the app from locating or syncing those products correctly.
According to Shopify's SKU guidelines:
"Don't use special characters, symbols, or spaces, because these can cause problems when searching for products in Shopify by SKU and in other computer programs."
Supported SKU Format
For the best compatibility, use only:
- Letters (A–Z)
- Numbers (0–9)
- Hyphens (
-) - Underscores (
_)
Examples
Valid SKU | Invalid SKU |
|---|---|
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How to Fix the Issue
- Open Shopify Admin → Products.
- Edit the affected product.
- Update the SKU by removing:
- Spaces
- Special characters (such as
#,@,&,/,*, etc.)
- Use only letters, numbers, hyphens (
-), or underscores (_). - Save the product.
- Return to the Duplicate SKU Sync app and search or sync the SKU again.
Important Notes
- Shopify API limitations affect SKU searches across all apps, not just Duplicate SKU Sync.
- Renaming the SKU to a supported format usually resolves the issue immediately.
- Consistent SKU formatting also improves compatibility with Shopify reports, imports, exports, and third-party apps.
Tip: Use simple, standardized SKU formats (for example,
ABC-123orSKU_001) to ensure reliable searching, syncing, and inventory management across Shopify and connected applications.