If multiple users are using the QB and if setting up of hosting cannot be done, then QuickBooks Error H505 occurs in your system. For resolving this issue, you need to follow the steps that are given below:
First, change the firewall settings of your system.
Even check the hosting configuration of both user and server system.
Create the new folder on the host computer for QB files and then share it by setting the permission.
Even after executing these steps if the error persists, then you need to consult the professional via QuickBooks customer care number. This number stays available at all 24 hours to guide their customers and help them in resolving all issues related to QuickBooks software.
Solved: What is QuickBooks Error H505 How to fix it