Thanks for reaching out to us here, @mastoroudes100-o.
Let me share some information about importing .iif files. To verify, are you trying to migrate your QuickBooks Desktop (QBDT) file to QuickBooks Online (QBO)? If so, you'll want to follow the detailed steps found in this article to transfer your file: Move your QuickBooks Desktop file to QuickBooks Online.
However, if you're importing .iif files directly into QBO, you'll need to convert them to .CSV file first. You can check on the website for third-party applications that can handle file transfer from .iif to .CSV.
I'll be adding these articles for your reference. You'll also see steps to guide along. Feel free to check.
Reach out to me if you have follow-up questions or concerns with importing your file. I'll be here to help. Have a wonderful day ahead.
Which QB Desktop country version do you have? If you are using QB Desktop US version, you can only migrate to QBO US version.
If you are using QB Desktop US version and need to migrate data to QBO South Africa version, you may have 2 ways:
1. Utilize a migration tool. i.e TPExporter for Desktop, TPImporter for Online.
2. Purchase a 3rd party conversion service.
Contact us in private for details.