the headers already sent error means that there is output to the page before the session_start function is being called.
if you examine the error, it reports the out pout coming from around line 7 of the index.php page:
output started at /home/gspa/public_html/index.php:7
ussually, the issue is caused by a blank space after a closing php tag:
or a blank line between a closing php tag and the next opening php tag:
if you have difficulty finding the cause of the problem, send a copy of the file in a zip archive so i can see the code.