QuickBooks error H303 is part of the H-series errors and typically occurs when transitioning to multi-user mode. Error code H303 displays an error message stating, This company file is on another computer, and QuickBooks needs assistance connecting. QuickBooks requires a network connection for access when attempting to open a company file located elsewhere.

This error prevents you from hosting your company file on a multi-user network, indicating an obstruction in establishing a connection to your server for multi-user access. To understand more about this error and how to troubleshoot it, please read through this comprehensive blog to the end. Ensure to carefully follow each step-by-step solution provided.

For quick assistance, we recommend connecting with our team of QuickBooks experts at a toll-free number 1.855.856.0042. Our experts are available to provide you with the best guidance and support. Feel free to reach out to resolve your QuickBooks issues efficiently.

What causes the multi-user mode Error in QB?

Several factors may cause error code H303 when transitioning to multi-user mode. Read these points to familiarize yourself with them.

• Incorrect configuration of Windows firewall settings.
• QuickBooks Database services might not running on your server computer.

Recommended to Read: How Do I Fix QuickBooks Error Code 6000

Best Solution to Resolve Multi-User Mode Error in QuickBooks

Here are the top solutions for resolving error code H303 and successfully hosting your company file in a multi-user connection.

Solution 1: Adjust Your Firewall Connection Settings

Improper configuration of Windows firewall settings may block QuickBooks files, hindering multi-user connections. Follow the steps below to adjust these settings.

• Open the Windows Start menu by pressing the Windows icon key on your keyboard.
• Type Windows Firewall in the search box and open it.
• Navigate to Advanced Settings and right-click on Inbound Rules.
• Click on New Rule to create a new rule.
• Choose Port and click Next.
• Choose TCP and provide the precise local ports to use:
• QuickBooks Desktop 2020 and later: 8019, XXXXX.
• QuickBooks Desktop 2019: 8019, XXXXX.
• QuickBooks Desktop 2018: 8019, 56728, 55378-55382.
• QuickBooks Desktop 2017: 8019, 56727, 55373-55377.
• Click Next and choose Allow the Connection.
• Click Next to ensure all profiles are checked. Then click 'Next' again.
• Name the rule as QBPorts(year) and click Finish.
• After creating the rule, try hosting your company file in a multi-user network again.

Read More: If You Cannot Open Company File in QuickBooks, Try This Fix

Solution 2: Verify That QuickBooks Services Are Running on Your Server Computer

The QuickBooks Database Server Manager services facilitate hosting the company file on a multi-user network. If these services are not running, it can disrupt hosting and lead to this error.

• Open the Windows Start menu on the computer that serves you. 
• Enter Run in the search bar and press Enter.
• In the Run dialog box, type services. msc and press Enter.
• Find and click on QuickBooksDBXX in the list of services and double-click to open its properties.
• Set the Startup Type to Automatic.
• Check the service's current status. It should be either Running or Started. If it's not, click on Start.

The solutions provided above should effectively resolve QuickBooks error H303. If these solutions are not helpful or users get the issue of the QBCFMonitorService not running on this computer please call a toll-free number 1.855.856.0042 to connect with a QuickBooks expert. They can assist you further.