doubt on while registering an email to sql server 2005

hi

i create one registration for as my own.i will create a table in that username varchar(50),password varchar(25),email id varchar(50).i should take these are the datatypes
username and password are correctly stored.in the email it will be atored as system.web.controls.webcontrols.textbox.

for what reason it will happen

sankarreddy