You may upload older PHP scripts that have the file extension .php3. However, if you are creating or editing a PHP file using the PHP Editor, we recommend that you save your file with the extension .php.

You will not be able to save your PHP files with the .html extension. Be sure to rename any PHP files you have already created using this extension.

PHP include files can use the .inc extension; however these files will not be read by the PHP interpreter. Because include directories may contain sensitive data, we recommend that you password-protect these directories.