It take serveal times and open cases to QB service about bank error message 9999 problem. but it have no response till now. Does it is a difficult problem for QB?

Try opening your QBO account on any private/incognito browser. If the same error persists, you can use MT Online or one of the converter tools (e.g csv2qbo @ $60 one time license) as a workaround.

https://www.moneythumb.com/?ref=110

Hi there, kelvin.

I understand the importance of resolving this matter promptly, particularly when it involves your banking in QuickBooks Online. I'll give you some insights into banking issues and how to resolve them right away.

But, before we proceed, could you please provide me with the specific error code and the name of your financial institution? This will allow me to confirm whether or not there are any ongoing investigations into your banking issue.

In the meantime, you can use this article as a reference for resolving bank errors or if you're having trouble downloading your transactions: What to do if you get a bank error or can't download transactions in QuickBooks Online.

Furthermore, I recommend reaching out to our Support Team once again and providing them with any relevant updates or additional details about your case. They will be able to provide you with the most accurate information regarding the status of your case and offer further assistance in resolving the bank error.

Feel free to let me know if you have other banking questions or concerns. I'd be glad to assist.