QuickBooks Error H505 has various reasons.
It’s possible that the QuickBooks Database Server Manager is inactive.
Sometimes incorrect hosting configuration settings prevent QuickBooks from connecting to the company file on the server.
It is conceivable that QuickBooks won’t connect to the server if the network data (.ND) is damaged.
This error may arise if you’re not able to obtain the host system’s IP address.
Another potential contributing element to the problem appears to be incorrect DNS settings.
QuickBooks is unable to connect to the server as a result of restrictive Firewall settings.
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