Solution 1: Check Hosting Settings
Verify Hosting Settings:
Open QuickBooks on the computer where the error is occurring.
Go to "File" > "Utilities" and ensure that "Host Multi-User Access" is selected.
If you see "Stop Hosting Multi-User Access," click on it.
Restart QuickBooks Database Server Manager:
Close QuickBooks on all computers.
Restart the QuickBooks Database Server Manager on the server computer.
Solution 2: Resolve Conflicts with Third-Party Security Software
Temporarily Disable Security Software:
Temporarily disable antivirus or security software on the server computer.
Attempt to open the company file on the affected computer.
Solution 3: Check Firewall Settings
Configure Firewall Settings:
Configure your firewall settings to allow QuickBooks communication.
Add QuickBooks executables to the exceptions list in your firewall.
Solution 4: Use QB Database Server Manager
Open QB Database Server Manager:
On the server computer, go to the Windows "Start" menu.
Search for "Database Server Manager" and open it.
Locate your company file in the "Scan Folders" tab and make sure it is listed.
Verify Services:
Press the Windows key + R to open the Run dialog.
Type services.msc and press Enter.
Ensure that the QuickBooksDBXX service is running, where XX represents the version of QuickBooks (e.g., QuickBooksDB28 for QuickBooks Desktop 2018).
Greetings,
Peter