The OP says that the email gets sent, which indicates that the script is running. That is why I don't (although originally I did) think it is just outputting the contents of the .pl file. If it were not for the statement that the email was sent, I would have given (and in fact did) the same response. If the script were not being run, which it would not if it had the wrong extension, it would not be sending the email. That is all I meant. Although, I do agree that my wording is very clunky and not at all clear.

Ok, I'll eat crow. I didn't read the extra link you posted. I will concede that this could be the issue.