Error message QBDBMgrN not running on this computer appears on your computer window when a multi-user mode error gets triggered. The error can get triggered due to various reasons such as improper installation of QuickBooks, issues with the firewall, or QuickBooks Database Server Manager. The solutions depend upon the cause of the error; therefore, there don?t be too disappointed if a solution doesn?t help. If you are stuck with the error and looking for quick-fix solutions, this article is for you. Read the complete article to find the solution that suits your situation. Dial 1.800.579.0391 if you need any technical assistance with the error?s troubleshooting.