QuickBooks Error 6189 and 816 typically occur when there are issues with the company file or network configuration. These errors can prevent users from accessing or opening their QuickBooks company files. Common causes include file corruption, network issues, or problems with the QuickBooks database server manager. To resolve these errors, try running the QuickBooks File Doctor tool, checking network connections, or verifying the file location. For further assistance, dial 1.855.738.2784.