What are the causes of QuickBooks Error H505?

1

Open QuickBooks on any workstations where you see H101, H303, or H505.
Don’t open your company file. Instead, select the File menu and hover over Utilities.
If you see the Host Multi-User Access option, don’t select it. Move on to the next workstation. This one isn’t causing the problem.
If Stop Hosting Multi-User Access is an option, select it.
Repeat these steps on all workstations where you see Error H101, H303, or H505.
After you check your workstations, move on to your server computer. This is the computer that normally hosts your company files.
Open QuickBooks on your server computer.
Open the File menu and hover over Utilities.
If Host Multi-User Access is an option, select it. If Stop Hosting Multi-User Access is an option, don’t select it.

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