QuickBooks: COMException: A QuickBooks company data file is already open and it is different from the one requested or there are multiple company files open.
- System.Runtime.InteropServices.COMException: A QuickBooks company data file is already open and it is different from the one requested or there are multiple company files open.
If you do not use multiple companies, and if a different company is not open in QuickBooks, then this error may be resolved by restarting the machine where Sync & Save is installed.