In our in-house lab and real-world experiments, when a network is set up as a peer-to-peer hosting environment (one of the computers hosts and uses the QuickBooks database while other users connect to the computer acting as a host) QuickBooks will throw error 80070057 if the database is opened by the computer hosting the file first. If another user opens the database first, no error occurs.
Currently known solutions:
1.) Always open the file on a system that is not the host computer before the host system opens the file.
2.) Add another system to only host the database instead (creating a dedicated server environment)