Hi @Anonymous
Is there another 2019 AutoCAD-based software installed on your PC? Or was it installed and later removed?
When a 2019 AutoCAD (or AutoCAD toolset) is installed on a system, the AutoCAD install path gets set via this registry key: HKEY_LOCAL_MACHINE\SOFTWARE\Autodesk\AutoCAD\R22\InstalledProducts
Any subsequent installations of AutoCAD or AutoCAD verticals from the same product/year will automatically install to the location specified in the Default value in the above registry key.

You can modify the value for Default under HKEY_LOCAL_MACHINE\SOFTWARE\Autodesk\AutoCAD\R22\InstalledProducts to point to the folder/drive where you want the software installed.
Warning: Improperly editing the Windows registry could render your operating system unusable. Use the Microsoft® Registry Editor at your own risk and only after backing up the registry. Microsoft provides critical information about the registry in the Microsoft Knowledge Base at http://support.microsoft.com/support.
NOTE: When you uninstall AutoCAD or an AutoCAD vertical you need to make sure that the Default value in the above registry key points to the install path of the program you are uninstalling. The uninstall will fail if it points to a different install path.