According to Intuit, Error Code H303 indicates that the computer on which the QuickBooks company file is located needs additional configuration. This error code has multiple possible causes:
- security software (e. g., a firewall) is blocking access to computer where the company file is located
- QuickBooks can’t obtain the Internet Protocol (IP) address of the computer where the company file is located
- the .ND file is damaged
- incorrect hosting configuration settings
There are a number of troubleshooting steps to resolve this error that are discussed in detail in the Intuit knowledge base article linked below. Several of these steps involve checking the Hosting setting. To verify the Hosting setting, press F2 while QuickBooks is running to display the Product Information window. The Local Server Information block shows the Hosting setting at the lower left of the window.
For more information on resolving Error Code H303, consult this Intuit knowledge base article.