When you open a company file in multi-user mode, you see an error:

• You're trying to work with a company file located on another computer, and this copy of QuickBooks can't reach the server on that computer (H202).
• It appears that the QuickBooks software on computer [server name] is set up to allow shared connections to the company file, but the QuickBooks software on your computer is unable to communicate with it (H202).
• You're trying to work with a company file located on another computer, and that computer needs additional installation and setup. (H101, H303, and H505).

Note: Intuit does not support firewall or anti-virus programs. You may need to consult the program provider for assistance with installing and setting up your program.

Why is this happening

QuickBooks Desktop is trying to establish a connection to the company file and can't communicate with the server (computer hosting the QuickBooks files).Several issues can cause the following:

• Hosting configuration settings are incorrect - Another computer might have hosting turned on. Only the server (where the file is saved) should have hosting turned on.
• QB firewall ports are not set properly - Firewall is blocking incoming/outgoing communication to the company file.
• The .ND file is damaged or incorrect - The .ND file is a configuration file that allows QuickBooks to access a company file in a network. A damaged .ND file may prevent QuickBooks Desktop from accessing files over the network.
• QuickBooks can't obtain the IP address of the host computer - QuickBooks Database Server Manager might be using a different/bad IP address.
• DNS settings are incorrect - Workstations are configured to open the file through the hosts’ Full Qualified Domain Name (ex. computername.domain.com).
• QuickBooks services are not started - QuickBooksDBXX or QBCFMonitor services are not running and should be started automatically.

How to fix it

Resolve QuickBooks Desktop errors: H101, H202, H303, and H505Intuit recommends several solutions for resolving errors. The first solution may solve your problem, or you may need to try all of them to resolve the issue. For best results, perform the solutions in the order shown.Important: These steps are highly technical in nature and may be best performed by a qualified IT professional present. The scope of this test is to see if QuickBooks can reach the server from the workstation(s). Ensure Network Discovery is turned on before performing the following steps:
To turn on Network Discovery:

1. Open Control Panel, click System and Security, and then click Windows Firewall.
2. In the left pane, click Allow an app or feature through Windows Firewall (if you are running Windows Server 2012).