A QuickBooks company data file is already open and it is different from the one requested.

Please make sure that you open QuickBooks the same way that you have specified under QuickBooks section in AdvancePro. For e.g.: If your path is C:\Program Files\Intuit\ *.qbw you would open QuickBooks by going to:

My computer C:\ Program Files Intuit Then double click on the QuickBooks file; *.qbw