You receive the following error when attempting to connect to QuickBooks Desktop:
"Error Executing Quickbooks Get; Caused by: 8004040a (Unknown error) : A QuickBooks company data file is already open and it is different from the one requested or there are multiple company files open."
This is most commonly caused by not specifying the correct QuickBooks company file location in the Connection component. If you do not specify the location, the Atom will try to connect to the currently open QuickBooks session.
The error indicates that QuickBooks is already open and the file is different from the one requested, or there are multiple instances of QuickBooks running.
The QuickBooks desktop edition has the unattended mode setup as per "Locate a company file" that is configured in the QB connection component.Please try closing QuickBooks and connecting again, or changing the setting back to use the default "Use the Company file that's open in QuickBooks".