QuickBooks software

Intuit recommends that all integration between QuickBooks and third-party software applications be implemented using the QuickBooks Software Development Kit (QBSDK). Intuit will support QuickBooks for customers who use applications which utilize the QuickBooks SDK...

Intuit expects to drop IIF from future versions of QuickBooks. Any such change will be announced in advance on this FAQ page.

4. What happens to the Intuit Interchange Format (.iif) integration?
Importing incorrect IIF files can lead to corruption of QuickBooks company files. Therefore, Intuit strongly discourages relying on IIF files for application integration. Intuit cannot support customers who have used IIF files created by third-party applications.

Notice to QuickBooks IIF import users from Intuit

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