If you wish to change the installation path or the specific components that are installed by the MySQL Installation Wizard, choose the Custom installation type.
To avoid having user data removed unintentionally during an upgrade, do not use the server installation folder as the destination folder for the server data files, which you can configure in the MySQL Server 5.5 Setup dialog.
A tree view on the left side of the custom install dialog lists all available components. Components that are not installed have a red X icon; components that are installed have a gray icon. To change whether a component is installed, click that component's icon and choose a new option from the drop-down list that appears.
You can change the default installation path by clicking thebutton to the right of the displayed installation path.
After choosing your installation components and installation path, click thebutton to advance to the confirmation dialog.