Okay I did that but I'm still getting the same error. It doesn't look like it updated the mail_php.php file but it did update the mailformatting_php.php file.
Here are the 3 files.
Your friends over here at WebAssist! These Dreamweaver extensions will assist you in building unlimited, custom websites.
These out-of-the-box solutions provide you proven, tested applications that can be up and running now. Build a store, a gallery, or a web-based email solution.