Hello there, accounts1.

This error can be caused by one these reasons:

• More workstations are open than the number of licences you've bought.
• A log file is pinned and the workstations need to be rebooted.
• A firewall is blocking the client workstation from the server.

We'll try some solutions to fix the issue.

First, let's verify the number of licensed users. Here's how:

1. Open QuickBooks.
2. Press F2 on the keyboard.
3. Check the number of licensed users in the User licenses row.

If the number of users are less than expected, please contact QuickBooks Technical Support to have your account checked. They can verify how many licensed users can access the software. Here's how to contact them:

1. Visit our website: https://help.quickbooks.intuit.com/contact.
2. Choose QuickBooks Desktop.
   
3. Choose the Desktop version.
4. On the Contact us page, choose a topic.
5. Click the Get Phone Number button.

Though, if the number of users is enough, let's re-setup multi-user environment .

Lastly, configure firewall and internet security settings.

Please let me know how it goes after trying these steps. I'll be here if you need further help.