I want to thank you, @drmorganjr, for all your efforts in trying to resolve the multi-user mode issue. I understand how hard it must be for you to be unable to open the sample file.

Let me provide insight on why the multi-user mode might not be functioning properly in QuickBooks Desktop (QBDT).

Here are some possible reasons why your QuickBooks multi-user mode is not working:

• The hosting settings may not be configured correctly.
• The firewall or antivirus software doesn't allow communication between user computers.
• QuickBooks may not be installed on the server.
• There could be an issue with opening the company file in the database server.
• Windows file permissions may not be set correctly.

However, since you've already tried all troubleshooting steps to get the multi-user mode to work and are unable to open even the sample file, I recommend reaching out to our support team for further assistance in identifying and resolving this issue.

Here's how to contact them:

1. Click the Help menu.
2. Select QuickBooks Desktop Help/Contact Us.
3. Enter a brief description of your concern, and select Continue.
4. Sign in to your Intuit Account, and select continue.
5. Select chat with us or Have us call you.

For reference, you can check this article: Contact QuickBooks Desktop support

I've also included a detailed resource about QuickBooks crashing which may come in handy moving forward: While working in QuickBooks, QuickBooks closes unexpectedly (crashes with or without an error)

Your patience on the matter is well appreciated. If you have any questions, feedback, or concerns regarding the issue of Multi-user mode, please don't hesitate to come back to the Community, @drmorganjr. I'll be here to assist you.