Hello Nonee!

You'll need to configure both the server and the workstations. This is to ensure that both computers will be able to run QuickBooks Desktop without issues.

Also, it's best to seek some assistance from your IT personnel so they can further assist you with it. You check this article and follow the steps on Step 3: Configure firewall manually section: Set up firewall and security settings for QuickBooks Desktop.

Post again here if you need more help. Take care!