If QB Database Server Manager faces an issue, you won't be able to use the Multi-User mode. So, to fix the QBDBMgrN Not Running error, you have to restart your QuickBooks Database Server Manager on your system. The steps to restart it are given below:

• First, press the Windows +R on the keyboard to get the Run window on the screen.

• Type Services.msc and hit Enter.

• Then scroll down and look for QB services listed there. You will find either of these- QuickBooksDB28, QuickBooksDB27, or QuickBooksDB26.

• Click right on the service you find and choose the option to Restart.

• Open QB again and check for the error status.

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