Moved new site from host gator to my dedicated server

I have moved my clients site from hostgator to my dedicated server however when I goto access his site it downloads the home page. this is a php issue but i have php and wordpress working across the server.

I cannot figure out why the php is not loading on this site.

any ideas would be great. This site was restored from a Full backup file and everything is loaded fine I just cannot find where the php issue is.

the site is live at (hostgator)

this is the site that will be the above once it is live.