If you saw just blank page on place of Install wizard, there could be more reasons:
php5 is not installed on your server - not each web server has installed PHP5 by default - please contact your server administrator to configure PHP5 with your web server.
php crashed during execution before any text was output to browser - reason should be possible to find in web server error log (often php crash e.g. if not correct versions of libraries/extensions are with php or any extension is missing)
In PHP5 you need minimum extensions: mysql, iconv, mbstring, gd2