Introduction: In this article I will explain how to send email using asp.net. Description: In Realtime we will use Gmail, yahoo, Hotmail etc to send mails to particular user here I will show to how to implement mail sending concept in asp.net. To implement mail concept in asp.net first we need to add following reference to our applicationSystem.Web.Mail namespace  What is System.Web.Mail System.Web.Mail is a namespace which contains classes that enable us to construct and send messages using the CDOSYS (Collaboration Data Objects for Windows 2000) message component. The mail message is delivered either through the SMTP mail service built into Microsoft Windows 2000 or through an arbitrary SMTP server. How we can get this reference (System.Web.Mail)  We need to add System.web.dll reference to our application for that follow below steps  a)  On the Project menu, click Add Reference. b)    On the .NET tab, locate System.Web.dll, and the...