Company didn't support QB 2016 and older version anymore. It would be too risky to run unsupported QB version on supporting Windows OS. If user doesn't have any plans yet to upgrade their QB to any supporting version, consider to keep running with the current system. Otherwise, consider upgrading it to QuickBooks Enterprise 2020 (with a subscription license) or downgrade it to Premier 2020 (with a one-time license).
The top priority when you upgrade QuickBooks Desktop is to make sure the database server meets the system requirements. The Windows Server 2019 works properly with QuickBooks Desktop Enterprise 20.0. Let me guide you on how to upgrade QuickBooks so you'll be able to get the best experience using it.
If you have a QuickBooks Desktop subscription, you'll get a message when a new version is available once you open the system. When you're ready to start, here are the steps:
Select Upgrade Now.
Click the Keep old version on my computer checkbox if you want to keep your current version of QuickBooks.
Select Let’s go. QuickBooks downloads, installs, and registers the new version. It also creates an updated version of your company files.
Once finished, select Open QuickBooks.
Please note that the upgrade may take some time depending on your internet speed and size of your company files.
In case you don't see a prompt to upgrade, it means you made a one-time purchase of QuickBooks. You can still upgrade by visiting the Help menu, then select the Upgrade QuickBooks tool. Check out this article for the detailed steps: Upgrade to newer versions of QuickBooks Desktop Enterprise. It also contains information on how to perform the process if you don't see a prompt.
After upgrading, you can set up and install a multi-user network so you can share your QuickBooks data with your team members. Doing so will require you to adjust settings in QuickBook Desktop, Windows, and your server.