“QBDBMGRN Not Running On This Computer” is an error indicating that the QuickBooks Database Server Manager, which allows multiple users to access the company file, is not running. This issue prevents access to the company file in multi-user mode, potentially due to service stoppage, firewall settings, or other system conflicts. Troubleshooting involves restarting the service and checking firewall settings. Contact a QB support team at 1.855.409.2300 if you face any issues.