This page will help you to remove an installation of a script. (for eg. To remove an installation of WordPress just follow the steps given below to you)
1) Click on the Red Icon button.
2) After clicking on the Red Icon button you will be redirected to the page where you can remove an installation. If you wish to keep the Installation Directory, Database and Database User for that Installation uncheck the respective boxes. Now click on the Remove Installation button to remove the installation.