Let's get this resolved, aejones3.
You can try to toggle the database server to isolate this issue.
- On your server computer, open the start menu then type database.
- Click on QuickBooks Database Server Manager.
- If no folder locations are shown, click Browse and browse to the folder where you store your company file(s).
- Click OK.
- Click Start Scan, which will repair the firewall permissions to allow QuickBooks to communicate over your network and resolve your error.
- Once done, click Close.
Then, try opening QuickBooks in a multi-user mode.
If you are prompted with an exact error message when using the multi-user mode, you can check this article on how to resolve it: How to fix Error H202 and H505.
I want to ensure that this is taken care of for you, so please feel free to let me know how it goes. Have a great day!