The problem you are facing might be due to the problem that you are trying to attach a file directly from your C: drive. You should first upload the selected file to a folder on your server (where your application is hosted), and once the mail is sent, delete the attached file.
But in any case, if you are running your application from your local PC (http://localhost
), you should be able to send the attachment. It might be a security issue. Try to attach a file directly from c drive, e.g C:/Upload/SomeFile.txt
Do revert if you need further clarification.