QuickBooks Online sync error: One of the list elements assigned to this transaction has been deleted

Why the sync error occurs

This error occurs when a transaction is attempting to sync to QuickBooks Online, but there's a classification on the transaction that can't be located in QuickBooks Online, usually because it has been deleted. This classification type is specified in the sync error (customer, vendor, class, etc.).

How to fix the sync error

In QuickBooks Online, restore the classification referenced in the sync error:

1. Open the appropriate list (Vendor list, Chart of Accounts, Product/Service, etc.)
2. Select the checkbox for Include inactive
3. Select the item you need to undelete
4. Select Make active under the Action column
5. Sync again