556925 Joomla premature end of script headers index.php

My site was working fine and then yesterday, out of nowhere I received an internal server error 500. After running error logs I got the following three items (warn) RSA server certificate (cn) does not match server name (warn) mod_fcgid error sending data from fastCGI server (error) Premature end of script headers [login to view URL] I currently run a site on joomla 2.5.1, PHP 5.2 Every other path works fine except for the joomla path so I assume for some reason the index just needs tweaking, I don't know why this occured. My site is accessed by [login to view URL], so I am stuck and need help ASAP