Symptoms: The following errors are found in the web server error logs:

Connection reset by peer: mod_fcgid: error reading data from FastCGI server

Premature end of script headers: index.php

Solutions:  This is one of those frustrating errors that can take a long time to fix and may be dependent on multiple problems.  The solution that worked in my case was adding:

ini_set(‘zend.enable_gc’, 0); <<Below the <?php tag in the index.php

Why does this work?  There are known conflicts between zend and APC, if both are installed you may receive the above error, adding the above code into your php file should resolve your issue.

Other possible solutions:  Modify your php.ini to increase max_execution_time, post_max_size, and max_input_time :: IMPORTANT – Make sure you maintain a limit, no limit could result in massive resource usage.