Sending email problem

I'm a newbies of asp.net programmer.When i try a simple sending mail<br>code and execute it,but it can't work....and the output came out is:<br>{<br>Server Application Unavailable <br>The web application you are attempting to access on this web server is<br>currently unavailable. Please hit the "Refresh" button in your web<br>browser to retry your request.<br><br>Administrator Note: An error message detailing the cause of this<br>specific request failure can be found in the system event log of the<br>web server. Please review this log entry to discover what caused this<br>error to occur.<br><br>}<br><br>what wrong which my configuration.Can someone guide me....

Are you sure that the SMTP Service is running on the local server? Maybe you could paste your code in here so we could take a look at what you are trying.<p><hr size="1" width="50%" align="left" />dotNetBB Forum Developer<br><b><i>Building A Better Community, One Post At A Time</i></b><br><a href="http://www.dotnetbb.com" target="_blank">www.dotnetbb.com</a></p>