After installing wordpress on my web server, I subsequently installed a themes in public_html/wp-content/themes.

The problem is that when i click on an installed theme there is no preview. When I clickon activate it shows that my selected theme is activated

But when i visit the web site it is entirely blank.

Please help cos I am going out of my mind.
Wel i would have believed the theme was broken but i tried others even the deault theme doesnt work and gves me the same thing…nada!!!