If your script is using the mail() function and it isn't working, check and see if all the parameters the script uses in the mail() function is set properly. Make sure the email address you're sending the information to is valid as well, and check your spam folder to see if any of the emails it's sending ends up automatically filtered.
You also should set the "from" header as well because the default "from" header will often get rejected or cause the mail to end up in the junk folder.