Do not uninstall Tableau before upgrading. For details on upgrading, see Upgrading from 2018.2 and Later (Windows).
This article explains how to uninstall previous versions, after you've upgraded to a newer version.
Uninstalling and completely removing Tableau Server
There are two primary "uninstall" scenarios that Tableau Server
Uninstall Tableau Server: After you upgrade to a new version of Tableau Server you can uninstall your previous version to free up disk space. Continue reading for information about uninstalling Tableau.
Remove Tableau Server: If you want to complete remove Tableau Server from a computer, you can use a script provided by Tableau to remove Tableau Server and all related files. This removes all data as well as server components, so should only be done if you know you want to reset the computer to a pre-Tableau state. You might need to do this if Technical Support recommends this step when troubleshooting an installation problem. We recommend you create a backup of your data before removing Tableau. Save the backup file to a safe location on a computer that is not part of your Tableau installation. Completely remove Tableau Server without uninstalling any version first. The script will uninstall all existing versions found on the computer. If you have already uninstalled your existing version and now want to completely remove Tableau, you can find the script to do so in a temporary location. For more details, see Remove Tableau Server from Your Computer.
Uninstall a Tableau Server version
When upgrading from one TSM version to another, you must leave the earlier version in place until you have finished the upgrade. Then you can uninstall it.
Use Control Panel to uninstall an earlier version of Tableau Server after upgrading. Starting with version 2018.2, you can have multiple versions of Tableau Server installed at the same time. All installed versions are visible in Control Panel, but only one version is running (the running version will generally be the version you upgraded to, but if you have not completed the upgrade process it could be an earlier version). After completing the upgrade you can uninstall your previous version.
Important: Beginning with version 2018.2, uninstalling Tableau Server will not create a backup of your data. As a best practice, always create a backup of your data before upgrading or uninstalling Tableau. This ensures you can reinstall and restore the data if you decide you want to do this. Save the backup to a safe location on a computer that is not part of your Tableau Server installation.
To uninstall a version of Tableau Server:
Open Control Panel, click Uninstall a program, and locate the version you want to uninstall.
Be sure you select the correct version to uninstall:
Uninstalling previous versions of Tableau Server does not impact the running version and simply removes unnecessary files from those previous versions.
Do not uninstall the current, running version. Uninstalling the current, running version of Tableau Server stops server and removes server-specific files and folders, but may leave some elements behind. Uninstalling does not create a backup of your repository data.
With the Tableau Server version selected, click Uninstall.