Hello, I tried to install 6 times Drupal 7 in Virtual Box based on Ubuntu (tried with version 17.04 and 14.04) with different procedure for each one but always I get the same error in the install profile section of Drupal 7

An AJAX HTTP error occurred. HTTP Result Code: 200 Debugging information follows. Path: http://home4.com/install.php?profile=standard&locale=en&id=1&op=do StatusText: OK ResponseText: Drupal already installed | Drupal @import url(“http://home4.com/modules/system/system.base.css?0”); @import url(“http://home4.com/modules/system/system.admin.css?0”); @import url(“http://home4.com/modules/system/system.menus.css?0”); @import url(“http://home4.com/modules/system/system.messages.css?0”); @import url(“http://home4.com/modules/system/system.theme.css?0”); @import url(“http://home4.com/modules/system/system.maintenance.css?0”); @import url(“http://home4.com/themes/seven/reset.css?0”); @import url(“http://home4.com/themes/seven/style.css?0”); Drupal already installed To start over, you must empty your existing database.To install to a different database, edit the appropriate settings.php file in the sites folder.To upgrade an existing installation, proceed to the update script.View your existing site.

I don’t understand why, I tried different procedure of installation, edit permissions on database and the webserver folders but nothing, he write 31 tables on MySQL and it stops. Any ideas? Thanks for the help.