This error occurs if you have a different QuickBooks file open (in QuickBooks) than the file that Sync & Save expects to open. QuickBooks does not support opening a second company file from an Integrated Application like Sync & Save.

Resolution: Close QuickBooks or open QuickBooks to the correct company file.  If you want the Sync & Save job to connect to a different company file, clear the Company File field and run the job again while QuickBooks is open to the correct company.