not send the mail in server

Question

hi
 pls help me
am developed an web application. in my application i need to send email functionality.. when am run the application in local system mail was send sucdessfully but after hosting in to server my application getting the following  error..
The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.5.1 Authentication Required.
 if u want check pls click the following url
http://demo.spectrumsoft.info/
please help .. i need to host today so please help me
thanks in advance