I understand this isn't an easy process for you, @patr1ckl. I'm here to ensure you'll get past this issue to move data easily.
The error message you get when exporting QuickBooks Online data is likely due to a compatibility problem. Make sure to log in to your QBO account using a supported web browser. See this link for more information about it: System requirements for QuickBooks Online, Accountant, Payroll, and QuickBooks Self-Employed.
If the issue persists, I recommend getting in touch with our Customer Support team. This allows our team to investigate further and provide you with the best resolution.
Let me also add this guide for the complete steps in transferring data.
Please know that you can get back to me anytime if you need more assistance with migrating files or if you have othe QuickBooks queries in general. I'll be pleased to provide you with additional guidance. Keep safe and have a good one!
