I edited the apache httpd.conf file recently for the mod_rewrite to work. I don\'t know if this problem originated from that or not, but i\'m getting this problem from that
Check dos and unix file format. This problem is seen on linux platforms if dos file format is used. Use doc2unix command like below and then retry it should work dos2unix *.php
This solution for below problem
Wed Nov 12 07:50:19 2014] [error] [client IP1] PHP Warning: Unknown: failed to
open stream: Permission denied in Unknown on line 0
[Wed Nov 12 07:50:19 2014] [error] [client IP1] PHP Fatal error: Unknown: Failed
opening required '/var/www/html/index.php' (include_path='.:/usr/share/pear:
/usr/share/php') in Unknown on line 0