I did not expect to be able to successfully send an email over localhost, but I also did not expect to receive an error message. The problem that I am having is ascertaining whether or not there is an error in my code AND....what the following error information indicates:

The application could not run because of the following error: Details Type: ErrorException Code: 8 Message: Use of undefined constant Swift_SendmailTransport - assumed 'Swift_SendmailTransport' File: C:\xampp\htdocs\emerson_3\index.php Line: 43 Trace

0 C:\xampp\htdocs\emerson_3\index.php(43): Slim\Slim::handleErrors(8, 'Use of undefine...', 'C:\xampp\htdocs...', 43, Array)

1 [internal function]: {closure}()

2 C:\xampp\htdocs\emerson_3\vendor\slim\slim\Slim\Route.php(468): call_user_func_array(Object(Closure), Array)

3 C:\xampp\htdocs\emerson_3\vendor\slim\slim\Slim\Slim.php(1357): Slim\Route->dispatch()

4 C:\xampp\htdocs\emerson_3\vendor\slim\slim\Slim\Middleware\Flash.php(85): Slim\Slim->call()

5 C:\xampp\htdocs\emerson_3\vendor\slim\slim\Slim\Middleware\MethodOverride.php(92): Slim\Middleware\Flash->call()

6 C:\xampp\htdocs\emerson_3\vendor\slim\slim\Slim\Middleware\PrettyExceptions.php(67): Slim\Middleware\MethodOverride->call()

7 C:\xampp\htdocs\emerson_3\vendor\slim\slim\Slim\Slim.php(1302): Slim\Middleware\PrettyExceptions->call()

8 C:\xampp\htdocs\emerson_3\index.php(65): Slim\Slim->run()

9 {main}