Hello there, danc.

Thanks for joining this thread. Allow me to help provide some additional information about the company data file in multi-user mode. 

To answer your question, yes. One of the operating system requirements in QuickBooks Desktop 2019 is the Windows 10, all editions including 64-bit, natively installed1. You can use it when hosting your company data file in multi-user mode. 

For additional reference, you can check this article to learn more about the QuickBooks Desktop system requirements. 

If you need further assistance with the process, I encourage you to contact our QuickBooks Desktop Chat Support Team. They have additional tools to pull up your account and do a remote session. 

Here's how you can contact our chat support:

1. Select QuickBooks Desktop Help from the Help menu.
2. You can also press F1 on your keyboard to bring up the same Help Panel. 
3. In order to route you to the correct support expert, we need to know what type of question you have.
4. Click Continue.
5. We’ll provide you a few options. You choose which one is best for you.

This will get you on the right track. Don't hesitate to click the Reply button if you have other questions about the company data file in multi-user mode. Have a good one.