Problem:

Browser displays HTTP:500 - The website cannot display the page when submitting a form and running a script in cgi-bin.

(8)Exec format error logged in $ErrorLog/error_log

Resolution:

This happens because Apache expects to run an executable and finds a script.  You need to add a #!  to the top of the script to tell UNIX to execute that script using the interpreter specified.

for example:

#! /bin/sh