Uninstall Old Versions of SQL Server Express
Once a newer version of SQL Server Express has been installed, it’s a good idea to uninstall any unused older versions.
Be sure older SQL Server Express versions are not being used by other applications prior to uninstalling.
Open the Control Panel.
Select Programs and Features or Uninstall a Program.
Locate and select the old version of Microsoft SQL Server.
Select Uninstall.
Repeat steps 3 – 4 when multiple older SQL Server Express versions are present.