Forum all white pages
 

My whole site has gone blank, I am in the admin control still but none of the forums pages or home page show anything more than white.

I was looking at the style manager just changed to 4.2 and saw a default mobile style I checked it's box while my other style was still checked and hit save display order and when to see the sites front page and it is just white.. Punched in the address for the forums same thing..

Any help would be great.