How QuickBooks Desktop (IIF Export) Works

Source: quickbooks_controller.rb

Export requires ALL account mappings and tax settings to be fully configured — if any mapping is missing, the export fails with a validation error
There is a 1-hour cooldown for identical exports to prevent accidentally sending the same data twice
Batch size is configurable per company, with a default of 25 records per export file
The export file is emailed to the company email as an IIF attachment — it is NOT available as a download from the Workshop interface
After a successful export, each record is stamped with a quickbooks_exported date to prevent re-exporting
Only closed and finalized invoices and credits are included in the export — open or draft invoices are excluded
Tax status (TAXABLE) is determined by combining both the item-level tax-free flag AND the customer-level tax-free status — both must allow tax for the line to be marked taxable
QuickBooks date format is MM/DD/YYYY regardless of the Workshop company's locale

"I didn't receive my QuickBooks export email" → Check that a company email is configured. The IIF file is sent as an email attachment, not downloaded. Also check spam folders. If the export was attempted less than 1 hour ago with the same data, it may have been blocked by the cooldown.
"Some invoices are missing from the export" → Only closed/finalized invoices and credits are exported. Open invoices and drafts are excluded. Also check that the invoices haven't already been exported (quickbooks_exported date would be set).
"Tax isn't showing on some line items in QuickBooks" → Tax status requires BOTH the item AND the customer to not be tax-free. If either is marked tax-free, the line is exported as non-taxable.