QuickBooks Desktop Sync Issue: Invoice Has a Line Item with a Duplicate ID

While Maxio pulls Invoice data from your QuickBooks Desktop company file, a sync can fail with this message: "The Invoice '...' has a line item with a duplicate ID. You may need to delete the Invoice then sync again." Maxio substitutes the actual Invoice number for the ellipsis.

You can see an example of this message in the QuickBooks Sync Issues tab.

Why QuickBooks Desktop sends a duplicate line item ID

Maxio builds a unique internal identifier for each Invoice Line Item from three pieces: the Invoice number, its QuickBooks transaction ID, and the line's own ID as reported by QuickBooks Desktop. Maxio's database enforces that identifier as unique. If your QuickBooks Desktop company file reports two line items on the same Invoice using the same internal line ID, Maxio's attempt to save the second line collides with the first, and the sync stops with this error. Because a QuickBooks Desktop transaction ID only ever applies to one Invoice, this collision happens between two line items on the same Invoice, not between two different Invoices.

This is an uncommon issue, and the reason your QuickBooks Desktop company file produced a duplicated internal line ID sits inside QuickBooks Desktop itself. Maxio's own sync process guards against two Web Connector sync sessions running against the same company file at once, so someone starting a sync while one is already in progress gets a "busy" response rather than causing this particular error.

Delete and recreate the Invoice in QuickBooks Desktop

Because the duplicate ID originates in QuickBooks Desktop, correcting the Invoice in Maxio alone doesn't fix it. Resolve the underlying Invoice in QuickBooks Desktop, then let it sync into Maxio again.

To resolve a duplicate line item ID error

1. In QuickBooks Desktop, open the Invoice named in the error message.
2. Delete that Invoice in QuickBooks Desktop.
3. Re-enter the Invoice in QuickBooks Desktop if you still need it on your books. Recreating it lets QuickBooks Desktop assign new, non-duplicated line IDs to each Item.
4. Run the QuickBooks Desktop sync again.

Related information

For the conditions that determine whether an Invoice syncs between Maxio and QuickBooks Desktop at all, see Sync QuickBooks Invoices.